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  • 1.
    Antzutkin, Oleg
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Kota, Hanumantha Rao
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Ikumapayi, Fatai
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Holmgren, Allan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Gunneriusson, Lars
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Johansson, Björn
    New Boliden AB.
    Berggren, Andreas
    New Boliden AB.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Öberg, Sven
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Hedlund, Jonas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Mouzon, Johanne
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Bhuiyan, Iftekhar Uddin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Forsmo, Seija
    LKAB.
    Interactions in multi-component mineral systems2011Conference paper (Other academic)
  • 2.
    Antzutkin, Oleg
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Kota, Hanumantha Rao
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Ikumapayi, Fatai
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Johansson, Björn
    New Boliden AB.
    Berggren, Andreas
    New Boliden AB.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Holmgren, Allan
    Öberg, Sven
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Hedlund, Jonas
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Mouzon, Johanne
    Bhuiyan, Iftekhar Uddin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Forsmo, Seija
    LKAB.
    Interactions in multi-component mineral systems2010Conference paper (Other academic)
  • 3.
    Gowda, Vasantha
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Laitinen, Risto S.
    Laboratory of Inorganic Chemistry, University of Oulu.
    Telkki, Ville-Veikko
    NMR Research Unit, University of Oulu.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Lantto, Perttu
    NMR Research Unit, University of Oulu.
    DFT calculations in the assignment of solid-state NMR and crystal structure elucidation of a lanthanum(iii) complex with dithiocarbamate and phenanthroline2016In: Dalton Transactions, ISSN 1477-9226, E-ISSN 1477-9234, Vol. 45, no 48, p. 19473-19484Article in journal (Refereed)
    Abstract [en]

    The molecular, crystal, and electronic structures as well as spectroscopic properties of a mononuclear heteroleptic lanthanum(iii) complex with diethyldithiocarbamate and 1,10-phenanthroline ligands (3 : 1) were studied by solid-state 13C and 15N cross-polarisation (CP) magic-angle-spinning (MAS) NMR, X-ray diffraction (XRD), and first principles density functional theory (DFT) calculations. A substantially different powder XRD pattern and 13C and 15N CP-MAS NMR spectra indicated that the title compound is not isostructural to the previously reported analogous rare earth complexes with the space group P21/n. Both 13C and 15N CP-MAS NMR revealed the presence of six structurally different dithiocarbamate groups in the asymmetric unit cell, implying a non-centrosymmetric packing arrangement of molecules. This was supported by single-crystal X-ray crystallography showing that the title compound crystallised in the triclinic space group P1[combining macron]. In addition, the crystal structure also revealed that one of the dithiocarbamate ligands has a conformational disorder. NMR chemical shift calculations employing the periodic gauge including projector augmented wave (GIPAW) approach supported the assignment of the experimental 13C and 15N NMR spectra. However, the best correspondences were obtained with the structure where the atomic positions in the X-ray unit cell were optimised at the DFT level. The roles of the scalar and spin-orbit relativistic effects on NMR shielding were investigated using the zeroth-order regular approximation (ZORA) method with the outcome that already the scalar relativistic level qualitatively reproduces the experimental chemical shifts. The electronic properties of the complex were evaluated based on the results of the natural bond orbital (NBO) and topology of the electron density analyses. Overall, we apply a multidisciplinary approach acquiring comprehensive information about the solid-state structure and the metal-ligand bonding of the heteroleptic lanthanum complex.

  • 4.
    Gowda, Vasantha
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Lantto, P.
    University of Oulu.
    Telkki, V-V
    University of Oulu.
    Öberg, Sven
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Structural investigations of rare earth dialkyl dithiocarbamate complexes: solid-state NMR, X-ray diffraction and DFT calculation studies2013Conference paper (Other academic)
    Abstract [en]

    In this study, we made an attempt to qualitatively study the structures of few rare earth metal complexes by employing solid state NMR, X-Ray Diffraction, and preliminary DFT calculations. High resolution 13C and 15N solid state CP/MAS NMR spectra were recorded for six diamagnetic polycrystalline rare earth dialkyldithiocarbamates of the general formula [(RE2S2CNR2)3 PHEN] (where RE=La or Y, R=C2H5, C3H7, and i-C3H7) [1]. Different isotropic 13C and 15N chemical shifts for the three dialkyldithiocarbamato groups were observed. Regulacio et al. (2005) inferred that irrespective of the alkyl chains, rare earth complexes of dialkyldithiocarbamates and phenanthroline (3:1) ligands always crystallize in a monoclinic system with a space P21/c group. However, comparative analysis of solid state 13C/15N CPMAS spectra of polycrystalline yttrium and lanthanum diethyldithiocarbamate complexes shows the presence of significant differences, indicating structural variations of these complexes. Also, quite different X-Ray diffraction powder pattern was observed for the above two complexes. Finally, the computational geometry optimization of Y and La complexes, followed by the preliminary calculation of 13C and 15N chemical shifts and shielding contributions with the ADF program [2], found to be very near to the experimental results.

  • 5.
    Gowda, Vasantha
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Lantto, Perttu
    University of Oulu.
    Modelling and structrual optimizations of rare earth coordination: First principles calculations2013Conference paper (Other academic)
    Abstract [en]

    An approximate 3D structure for the yttrium diethyldithiocarbamato-phenanthroline complex 1, obtained by manually replacing the Nd3+ ion with Y3+ion of the reported crystal structure for neodymium diethyldithiocarbamato-phenanthroline complex 2 followed by DFT geometry optimization using periodic boundary conditions with dispersion corrected functional, has been compared with DFT optimized structure for 1. The quality of the method is discussed by comparing predicted PXRD pattern, high resolution solid state 13C and 15N CP/MAS NMR data and calculated chemical shift tensor eigenvalues for optimized structures for 1 and 2. We have observed an excellent agreement between the ‘modeled’ and experimental structures. Finally, to take into account the relativistic effects on NMR shielding calculations, we have employed the zeroth-order regular approximation (ZORA) formalism using Slater-type orbital (STO) basis sets implemented in Amsterdam Density Functional (ADF) package. The present approach can be further extended to study other complexes of rare earth metals in general, particularly those having similar crystal structure.

  • 6.
    Gowda, Vasantha
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering. NMR Research Unit, University of Oulu.
    Sarma, Bipul
    Department of Chemical Sciences, Tezpur University.
    Laitinen, Risto S.
    Laboratory of Inorganic Chemistry, University of Oulu.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Ivanov, Alexander V.
    Institute of Geology and Nature Management, Far Eastern Branch of the Russian Academy of Sciences .
    Iuga, Dinu
    Department of Physics, Warwick University.
    Lantto, Perttu
    NMR Research Unit, University of Oulu.
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering. Department of Physics, Warwick University.
    Structural insights into the polymorphism of bismuth(III) di-n-butyldithiocarbamate by X-ray diffraction, solid-state (13C/15N) CP-MAS NMR and DFT calculations2017In: Polyhedron, ISSN 0277-5387, E-ISSN 1873-3719, Vol. 129, p. 123-132Article in journal (Refereed)
    Abstract [en]

    Two crystalline polymorphs of a binuclear tris(di-n-butyldithiocarbamato)bismuth(III) complex, I and II, with an empirical formula of [Bi{S2CN(n-C4H9)2}3] were synthesised and characterised by X-ray diffraction (XRD), solid-state NMR and density functional theory (DFT) calculations. At the supramolecular level, these mononuclear molecular units interact in pairs via secondary Bi⋯S bonds, yielding binuclear formations of [Bi2{S2CN(n-C4H9)2}6]. The polymorph I () contains two isomeric non-centrosymmetric binuclear molecules of [Bi2{S2CN(n-C4H9)2}6], which are related to each other as conformers, therefore having four structurally inequivalent bismuth atoms and twelve inequivalent dithiocarbamate ligands. In contrast, the structurally simpler polymorph II (P21/n) exists as a single molecular form of the corresponding centrosymmetric binuclear formation, comprising two structurally equivalent bismuth atoms and three structurally different dithiocarbamate groups. The polymorphs I and II were found to be interconvertible by altering the solvent system during the recrystallisation process. Sun et al. (2012) has reported a crystalline form of the title compound which resembles, but is not identical with, polymorph II. Experimental solid-state 13C and 15N cross-polarisation (CP) magic-angle-spinning (MAS) NMR spectra of both polymorphs I and II were in accord with the direct structural data on these complexes. Assignments of the resonance lines in the solid-state 13C and 15N NMR spectra were assisted by chemical shift calculations of the crystals using periodic DFT.

  • 7.
    Gowda, Vasantha
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Sarma, Bipul
    Department of Chemical Sciences, Division of Chemical Engineering, Tezpur University, Tezpur, Assam.
    Öberg, Sven
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Telkki, Ville-Veikko
    University of Oulu, NMR Research Group, Division of Chemical Engineering, Faculty of Science, University of Oulu.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Lantto, Perttu
    University of Oulu, NMR Research Group, Division of Chemical Engineering, Faculty of Science, University of Oulu.
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Structure Elucidation of an Yttrium Diethyldithiocarbamato-Phenanthroline Complex by X-ray Crystallography, Solid-State NMR, and ab-initio Quantum Chemical Calculations2016In: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, Vol. 20, p. 3278-3291Article in journal (Refereed)
    Abstract [en]

    We present a structural analysis method for molecular and electronic structure of yttrium diethyldithiocarbamato-phenanthroline complex {[Y(S2CNR2)3PHEN] with R = C2H5 and PHEN = 1,10-phenanthroline} combining solid-state NMR spectroscopy, XRD, and first principles DFT calculations. Replacing the Nd3+ ion with Y3+ in the reported crystal structure of [Nd(S2CNR2)3PHEN] complex generated an approximate 3D structure of the title complex. The structure was then subjected to first principles quantum chemical geometry optimisation using periodic DFT method. The quality of the method is discussed by comparing predicted and experimental powder XRD patterns. Full assignment of 13C and 15N solid-state CP-MAS NMR spectra as well as analyses of the principal values of the chemical shift tensors were carried out using periodic scalar relativistic DFT modelling. Spin-orbit relativistic effects, estimated by SO-ZORA formalism for one molecular unit, were evaluated. Finally, the X-ray structure of the title complex was determined, which proved that the former procedure is appropriate. The most important orbital interactions were investigated by Natural Bond Orbital analysis. The isotropic shielding values for S2CN-carbons were analysed by Natural Localised Molecular Orbital analysis. The present approach can be further extended to study other rare earth metal complexes, particularly those having similar but not yet solved crystal structures

  • 8.
    Ivanov, Alexander
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Korneeva, Eugenia V.
    Far Eastern Branch of the Russian Academy of Sciences, 675000, Blagoveschensk, Amur Region.
    Lutsenko, Irina A.
    Far Eastern Branch of the Russian Academy of Sciences, 675000, Blagoveschensk, Amur Region.
    Gerasimenko, Andrey V.
    Institute of Chemistry, Far Eastern Branch of the Russian Academy of Sciences, 690022, Vladivostok.
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Sergienko, Valentin I.
    Institute of Chemistry, Far Eastern Branch of the Russian Academy of Sciences, 690022, Vladivostok.
    A fixation mode of gold from solutions using heterogeneous reaction of cadmium dicyclohexyl dithiophosphate with H[AuCl4]. Structural and (13C, 31P) CP/MAS NMR studies and thermal behaviour of crystalline polymeric gold(I) dicyclohexyl dithiophosphate and bis(dicyclohexylthiophosphoryl) disulphide2013In: Journal of Molecular Structure, ISSN 0022-2860, E-ISSN 1872-8014, Vol. 1034, p. 152-161Article in journal (Refereed)
    Abstract [en]

    Two novel compounds: polynuclear catena-poly[bis(3-O,O’-di-cyclo-hexyldithiophosphato-S,S,S’)digold(I)] (Au–Au) (1) and crystalline bis(O,O’-di-cyclo-hexylthiophosphoryl)disulphide, (cyclo-C6H11O)2P(S)S–S(S)P(O-cyclo-C6H11) (2) were prepared using heterogeneous reaction between freshly precipitated binuclear cadmium(II) dithiophosphate (Dtph), [Cd2{S2P(O-cyclo-C6H11}4] and H[AuCl4] in 2 M hydrochloric acid. The isolated compounds 1 and 2 (the fixation mode of gold from the solution and the oxidised form of Dtph groups, respectively) have been studied by means of single-crystal X-ray diffraction, 13C and 31P cross-polarisation / magic-angle-spinning (CP/MAS) NMR spectroscopy and simultaneous thermal analysis (STA). Centrosymmetric binuclear molecule of 1, [Au2{S2P(O-cyclo-C6H11)2}2] comprises a pair of -bridging di-cyclo-hexyl Dtph ligands, linking two neighbouring gold atoms, and displays additional intramolecular aurophilic bond Au···Au. At the supramolecular level of structural self-organisation of complex 1, infinite polymeric zigzag chains arise due to pairs of the secondary bonds Au···S between neighbouring binuclear molecules. Centrosymmetric molecule of 2 displays two O,O-di-cyclo-hexythiophosphoryl fragments, which are connected by the chemical bond S(1)–S(1)a, and a planar zigzag array [S=P–S–S–P=S] passing through the central part of the molecule. To characterise additionally the Dtph groups in both compounds 1 and 2, chemical shift anisotropy (CSA) parameters (aniso and) were calculated from spinning sideband manifolds in experimental 31P MAS NMR spectra. The thermal behaviour of complex 1 was studied using simultaneous thermal analysis (a combination of TG and DSC) under an argon atmosphere. The thermal behaviour displays stepwise mass loss, comprising thermal decompositions of the organic and inorganic parts of 1 with gold(I) dithio-meta-phosphate and reduced metallic gold as the intermediate and the final products, respectively.

  • 9.
    Ivanov, Alexander V.
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Kritikos, Mikael
    Stockholm University.
    Forsling, Willis
    Polycrystalline and surface O,O′-dialkyldithiophosphate zinc(II) complexes: preparation, 31P CP/MAS NMR and single-crystal X-ray diffraction studies2001In: Inorganica Chimica Acta, ISSN 0020-1693, E-ISSN 1873-3255, Vol. 315, no 1, p. 26-35Article in journal (Refereed)
    Abstract [en]

    Dithiophosphate zinc(II) complexes with eight different O,O′-dialkyldithiophosphate ligands have been prepared in solid/liquid states and as surface complexes on a synthetic sphalerite, and studied by means of 31P NMR spectroscopy. All 31P resonances, corresponding to dithiophosphate ligands with different structural functions (i.e. terminal chelating or bridging between two metal atoms in bi- and tetranuclear complexes), have been assigned on the basis of comparative analyses of chemical shift data for solid complexes, their melts and chloroform solutions at various concentrations. The bridging coordination of O,O′-dialkyldithiophosphate ligands by the two neighbouring zinc(II) atoms was established in the case of zinc(II) complexes formed at the surface of the synthetic sphalerite. In addition, novel molecular and crystal structures of the binuclear O,O′-di-cyclo-hexyldithiophosphate zinc(II) complex have been resolved by single-crystal X-ray diffraction data analysis, and useful correlations with 31P NMR data for this complex were obtained.

  • 10.
    Ivanov, Alexander V.
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Forsling, Willis
    Kritikos, M.
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Zhukov, F. A.
    Yusupov, Z. F.
    Structural organization of zinc, nickel(II), and copper(II) O,O '-dicyclohexyl phosphorodithioate complexes as probed by X-ray diffraction, EPR, and solid-state high-resolution C-13 and P-31 NMR2000In: Doklady. Chemistry, ISSN 0012-5008, E-ISSN 1608-3113, Vol. 375, no 1-3, p. 236-241Article in journal (Refereed)
  • 11.
    Ivanov, Alexander V.
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Konfederatov, V.A.
    Institute of Geology and Nature Management, Far East Branch, Russian Academy of Sciences, Blagoveshchensk.
    Gerasimenko, A.V.
    Institute of Chemistry, Far Eastern Branch of the Russian Academy of Sciences, 690022, Vladivostok.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Polymeric thallium(I) O,O′-diisopropyl dithiophosphate [Tl{S2P(O-iso-C3H7)2}]n: synthesis, structure, and 13C and 31P CP/MAS2009In: Russian journal of coordination chemistry, ISSN 1070-3284, E-ISSN 1608-3318, Vol. 35, no 11, p. 857-863Article in journal (Refereed)
    Abstract [en]

    The crystalline polymeric thallium(I) O,O′-diisopropyl dithiophosphate [Tl{S2P(O-iso-C3H7)2}] n (I) was obtained and examined by solid-state 13C and 31P CP/MAS NMR spectroscopy. Diagrams of the χ2 statistic were constructed from the complete 31P MAS NMR spectra and used to calculate the 31P chemical shift anisotropy (δaniso = (δ zz - δiso)) and the asymmetry parameter (η = (δ yy - δ xx )/(δ zz - δiso)). The 31P chemical shift tensor has a nearly axial symmetry (η = 0.22, δ zz < δ yy ≈ δ xx ). The MAS NMR spectral patterns correspond to the negative sign of δaniso (δ zz < δ yy < δ xx ), which indicates bridging or chelating-bridging coordination of the dithiophosphate ligands (Dtph). X-ray diffraction analysis revealed a polymeric structure of compound I. The polymer chain consists of alternating mononuclear [Tl{S2P(O-iso-C3H7)2}] molecules with opposite spatial orientations. The Dtph ligands are coordinated in a mixed, chelating-μ3-bridging fashion. The shape of the 31P NMR signal was interpreted in terms of the 31P-203,205Tl coupling pattern proposed from crystallographic data.

  • 12.
    Ivanov, Alexander V.
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Rodionova, N. A.
    Blagoveshchensk State Pedagogical University.
    Gerasimenko, A. V.
    Institute of Chemistry, Far East Division, Russian Academy of Sciences.
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Forsling, Willis
    Structural organization of nickel(II) and copper(II) O,O'-dialkyl phosphorodithioate complexes as probed by X-ray diffraction, EPR, and CP/MAS 13C and 31P NMR2004In: Russian Journal of Inorganic Chemistry, ISSN 0036-0236, E-ISSN 1531-8613, Vol. 49, no 3, p. 373-385Article in journal (Refereed)
    Abstract [en]

    The nickel(II) and copper(II) complexes [M{S2P(OR)(2)}(2)] (M = Ni, Cu-63, Cu-65; R = C2H5, C3H7, i-C3H7, C4H9, i-C4H9, s-C4H9, i-C5H11, c-C6H11) with eight symmetric O,O'-dialkyl phosphorodithioates were synthesized, and their structures and spectral properties were studied by EPR and CP/MAS C-13 and P-31 NMR. As determined by EPR, the [CuS4] chromophores in the lattice of nickel(II) complexes have predominantly a square-planar structure. The chromophores in complexes with phosphorodithioate ligands incorporating bulky alkyl substituents have somewhat distorted geometries. NMR shows that the Dtph groups in most nickel(II) complexes are structurally equivalent. An exception is [Ni{S2P(OC3H7)(2)}(2)], which gives rise to two (1 : 1) P-31 NMR signals. For [Ni(S2P(O-i-C4H9)(2))(2)], the alpha and beta modifications were obtained. In the alpha modification, the phosphorodithioate groups are nonequivalent, whereas the P modification has structurally equivalent ligands. The broadening of the P-31 NMR signal of the [Ni{S2P(O-s-C4H9)(2)}(2)] complex is rationalized by the existence of six optical isomers (due to two chiral centers in each of the ligands). For the Dtph groups acting as bidentate terminal ligands in the nickel(II) complexes, the P-31 chemical shift anisotropy delta(aniso) and asymmetry parameter eta were calculated from experimental NMR spectra. Single-crystal X-ray diffraction shows that bis(O,O'-dipropyl phosphorodithioato)nickel(II) exists in the form of two centrosymmetric molecules. In the structure of alpha-bis(O,O'-dipropyl phosphorodithioato)nickel(II), the Dtph ligands in the molecule are nonequivalent. The experimental P-31 NMR signals in the spectra of [Ni{S2P(OC3H7)(2)}(2)] and alpha-[Ni{S2P(O-i-C4H9)(2)}(2)] are assigned to the structural positions of phosphorus atoms in the corresponding molecular structures determined by X-ray diffraction.

  • 13.
    Ivanov, Alexander V.
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Lutsenko, I.A.
    Institute of Geology and Nature Management, Far East Branch, Russian Academy of Sciences, Blagoveshchensk.
    Komeeva, E.V.
    Institute of Geology and Nature Management, Far East Branch, Russian Academy of Sciences, Blagoveshchensk.
    Gerasimenko, A.V.
    Institute of Chemistry, Far Eastern Branch of the Russian Academy of Sciences, 690022, Vladivostok.
    Ogil'ko, G.V.
    Blagoveshchensk State Pedagogical University.
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Binding of Au3+ from solutions by nickel(II) and cadmium diisopropyl dithiophosphates: MAS P-31 NMR, structure and thermal behavior of the polynuclear complex [Au-2{S2P(O-iso-C3H7)(2)}(2)] (n)2012In: Russian journal of coordination chemistry, ISSN 1070-3284, E-ISSN 1608-3318, Vol. 38, no 6, p. 430-439Article in journal (Refereed)
    Abstract [en]

    The paper deals with reactions of freshly precipitated diisopropyl dithiophosphate (Dtph) complexes of nickel(II), [Ni{S2P(O-iso-C3H7)(2)}(2)] and cadmium, [Cd-2{S2P(O-iso-C3H7)(2)}(4)], with the [AuCl4](-) in 2M HCl, resulting in gold transition from the solution to the precipitate as polymeric gold(I) diisopropyl dithiophosphate. The reduction of gold(III) to gold(I) noted in both cases is due to oxidation of the relevant part of the Dtph group to bis(O,O'-di-(iso)-propoxythiophosphoryl) disulfide, (iso-C3H7O)(2)P(S)S-S(S)P(O-iso-C3H7)(2). The polynuclear gold(I) complex [Au-2{S2P(O-iso-C3H7)(2)}(2)] (n) (I) was isolated on a preparative scale from the chemisorption system and studied by MAS P-31 NMR and X-ray diffraction. The key structural unit of I is the non-centrosymmetric binuclear molecule [Au-2{S2P(O-iso-C3H7)(2)}(2)] in which the gold atoms are connected by two bridging Dtph groups. The structure contains two types of non-equivalent binuclear molecules related as conformational isomers. Owing to the relatively weak Au-Au contacts, the neighboring binuclear [Au-2{S2P(O-iso-C3H7)(2)}(2)] molecules are involved in an infinite polymeric chain with conformer alternation along the chain. To elucidate the conditions for the recovery of bound gold(I), the precipitates formed in the sorption systems were studied by simultaneous thermal analysis under argon. As the final product, thermolysis gives reduced metallic gold. The ability of dithiophosphate complexes to bind gold from a solution is much lower than that of dithiocarbamate complexes, which is due to oxidation of some Dtph groups to disulfide.

  • 14.
    Ivanov, M.A.
    et al.
    Institute of Geology and Nature Management, Far East Branch, Russian Academy of Sciences, Blagoveshchensk.
    Gerasimenko, A.V.
    Institute of Chemistry, Far Eastern Branch of the Russian Academy of Sciences, 690022, Vladivostok.
    Ivanov, A.V.
    Institute of Geology and Nature Management, Far East Branch, Russian Academy of Sciences, Blagoveshchensk.
    Solozhenkin, P.M.
    Institute of Comprehensive Exploitation of Mineral Resources, Russian Academy of Sciences, Kryukovsky Tupik 4, Moscow.
    Sharutin, V.V.
    Southern Ural State University, Chelyabinsk.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Pushilin, M.A
    Institute of Chemistry, Far Eastern Branch of the Russian Academy of Sciences, 690022, Vladivostok.
    The diethyl dithiophosphate complex of tetraphenylantimony(V) and its solvated form, [Sb(C6H5)(4){S2P(OC2H5)(2)}] center dot 1/2 C6H6: Synthesis, crystal structure, and C-13, P-31 CP/MAS NMR study: an example of monodentate coordination of dithio ligands2013In: Russian Journal of Inorganic Chemistry, ISSN 0036-0236, E-ISSN 1531-8613, Vol. 58, no 2, p. 197-205Article in journal (Refereed)
    Abstract [en]

    The O,O'-diethyl dithiophosphate complex of tetraphenylantimony(V) [Sb(C6H5)(4){S2P(OC2H5)(2)}] (I) and its benzene-solvated form I center dot 1/2C(6)H(6) (II) were synthesized and studied by high-resolution solid-state C-13 and P-31 NMR (MAS NMR). The diethyl dithiophosphate (Dtph) groups in I and II were quantitatively characterized by the P-31 chemical shift anisotropy (delta(aniso)), the asymmetry parameter (eta), and the principal values of chemical shift tensors (delta (xx) , delta (yy) , delta (zz) ). The calculation of the anisotropy parameters included construction of chi(2) statistic diagrams from full P-31 MAS NMR spectra. In both complexes, the Dtph groups were found to have mainly axially symmetric P-31 chemical shift tensors (for delta (zz) < delta (xx) a parts per thousand delta (yy) ) with similar anisotropy parameters (delta(aniso) and eta), which is due to their identical S-monodentate function. According to X-ray diffraction data, II has a trigonal bipyramidal (TBP) molecular structure with Smonodentate coordination of Dtph in the TBP axial position and outer-sphere position of the benzene molecule. The desorption of the outer-sphere benzene solvent molecules from structure II, which was noted in MAS NMR experiment, passes through the formation of three intermediate solvated forms with benzene content n < 1/2.

  • 15.
    Korneeva, E V
    et al.
    Institute of Geology and Nature Management, Far East Branch, Russian Academy of Sciences, Blagoveshchensk.
    Rodina, T A
    Amur State University, Blagoveshchensk, Russian Federation.
    Ivanov, A V
    Institute of Geology and Nature Management, Far East Branch, Russian Academy of Sciences, Blagoveshchensk.
    Gerasimenko, A V
    Institute of Chemistry, Far Eastern Branch of the Russian Academy of Sciences, 690022, Vladivostok.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Polymeric Gold(I) Diisobutyl Dithiophosphate, [Au2{S2P(O-iso-C4H9)2}2]n: Synthesis, Supramolecular Self-Organisation (a Role of Aurophilic Interaction), 13C and 31P MAS NMR Spectroscopy, and Thermal Behavior2014In: Russian journal of coordination chemistry, ISSN 1070-3284, E-ISSN 1608-3318, Vol. 40, no 10, p. 748-756Article in journal (Refereed)
    Abstract [en]

    A new polymeric gold(I) diisobutyl dithiophosphate (Dtph), [Au2{S2P(O-iso-C4H9)2}2] n (I), was preparatively obtained and characterized by 13C and 31P MAS NMR spectroscopy and X-ray diffraction (CIF file CCDC no. 977818). Diagrams of the χ2 statistic were constructed from the complete 31P MAS NMR spectra and used to calculate the 31P chemical shift anisotropy (δ aniso = δ zz − δ iso ) and the asymmetry parameter η = (δ yy − δ xx )/(δ zz − δ iso ). The main structural unit of complex I is the noncentrosymmetric dinuclear molecule [Au2{S2P(O-iso-C4H9)2}2], in which the gold atoms are linked by two bridging ligands Dtph. The central cyclic structural fragment of the dimer [Au2S4P2] is additionally stabilized by the intramolecular aurophilic interaction Au⋯Au. Further supramolecular self-organization of the complex involves intermolecular aurophilic bonds Au⋯Au that serve to unite adjacent dinuclear molecules [Au2{S2P(O-iso-C4H9)2}2] with different spatial orientations into the polymer chains ([Au2{S2P(O-iso-C4H9)2}2]) n . The thermal behavior of complex I was examined by synchronous thermal analysis under argon. The character of the thermolysis of the complex to reduced metallic gold as a final product was determined.

  • 16.
    Korneeva, E.V.
    et al.
    Institute of Geology and Nature Management, Far East Branch, Russian Academy of Sciences, Blagoveshchensk.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Ivanov, Alexander V.
    Institute of Geology and Nature Management, Far Eastern Branch of the Russian Academy of Sciences .
    Novikova, E.V.
    Institute of Geology and Nature Management, Far East Branch, Russian Academy of Sciences, Blagoveshchensk.
    Smolentsev, A.I.
    Nikolaev Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk.
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Crystalline nickel(II) di-i-amyl dithiophosphate, [Ni{S2P(O-i-C5H11)2}2]: Preparation, structure, heteronuclear (13C, 31P) CP/MAS NMR spectra, and thermal behavior2017In: Russian journal of coordination chemistry, ISSN 1070-3284, E-ISSN 1608-3318, Vol. 43, no 4, p. 223-231Article in journal (Refereed)
    Abstract [en]

    The crystalline nickel(II) di-i-amyl) dithiophosphate (Dtph), [Ni{S2P(O-i-C5H11)2}2] (I) was isolated on a preparative scale and characterized by 13C, 31P MAS NMR, and X-ray diffraction (CIF file CCDC no. 1469369). The χ2-statistic diagrams were constructed from full 31P CP/MAS NMR spectra for calculating the 31P chemical shift anisotropy: δaniso = δzz–δiso and the asymmetry parameter η = (δyy–δxx)/(δzz–δiso). The key structural unit of I is the centrosymmetric [Ni{S2P(O-i-C5H11)2}2] molecule in which the nickel atom coordinates two Dtph ligands in the isobidentate fashion. In molecule I, each carbon, oxygen, and sulfur atom is statistically disordered over two sites with equal occupancies. However, the disorder does not affect nickel and phosphorus. These results were interpreted as the presence in I of two [Ni{S2P(O-i-C5H11)2}2] molecules rotated through 21.0(1)° (the angle between the [NiS4] chromophore planes) relative to each other around the bisecting P–Ni–P axis passing through both four-membered [NiS2P] rings. The two molecules occupy crystal lattice sites with equal probabilities. The thermal behavior of I was studied by simultaneous thermal analysis under argon. The course of the thermal destruction of the complex was established, nickel pyrophosphate (Ni2P2O7) was identified as the final product of thermal transformations.

  • 17.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    A nuclear magnetic resonance study of dialkyldithiophosphate complexes: polycrystalline and surface adsorbed2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    31P, 13C and 207Pb NMR were used to characterize different metal (Ni, Zn, Pb) dialkyldithiophosphate complexes. Eight different sodium or potassium dialkyldithiophosphate salts (alkyl groups R=ethyl-, n-propyl, iso-propyl, n- butyl, iso-butyl, sec-butyl, iso-amyl and cyclo-hexyl) were used as starting materials. The metal complexes studied are mononuclear, binuclear, tetranuclear or polynuclear and the structural diversity is reflected in different 31P chemical shifts and chemical shift aniostropies of the complexes. A correlation between the 31P chemical shift tensor principal value d22 and the S-P-S angle of the complexes was revealed. The ligands were also adsorbed on the surface of synthetic ZnS and PbS and studied by 31P CP/MAS NMR: spectra of the dry samples showed that in both cases chemisorption of the ligands on the mineral surfaces occured. The ligands chemisorbed on ZnS have a bridging coordination, while the coordination of the ligand to PbS is terminal. Products of oxidation and hydrolysis were also found on the mineral surfaces; disulfides were detected on the surface of ZnS and monothiophosphates and orthophosphates on the surface of PbS. After three months of storing of the PbS samples, more hydrolysis products were formed as well as precipitated lead(II) dithiophosphate complexes.

  • 18.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    A nuclear magnetic resonance study of polycrystalline and surface O, O´-dialkyldithiophosphate complexes2001Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    O, O'-dialkyldithiophosphate (dtp) complexes are known to be useful collectors of e. g. ZnS, PbS and CuS minerals in froth flotation. However, the precise surface chemistry is yet not understood. In this work model systems have been thoroughly studied by both liquid and solid state 31P NMR. Nickel and zinc dtp complexes have been precipitated from aqueous solutions of dtps and metal chlorides. Ionic sodium and potassium salts of eight different dtps have been used. The nickel complexes are known to be mononuclear with only terminal ligands while the zinc complexes are known to be binuclear or polymeric with both terminal and bridging types of ligands. In organic solvents the binuclear complexes dissolve into the mononuclear type which has only terminal ligands. There is also a tetranuclear type of zinc dtp complex where all ligands are bridging. By using solid state CP/MAS and liquid state 31P NMR together with analysis of the chemical shift anisotropy (CSA) it is possible to assign 31P resonance lines to different types of ligands. The least shielded 31P sites in zinc dtp complexes are assigned to the bridging ligands and the most shielded 31P sites to the terminal ligands. By comparing the spectra of precipitated complexes with the spectra of surface complexes it has been possible to assign a bridging coordination between two surface sites and the ligand. Traces of oxidized dtp, bis-(O, O'-dialkyldithio-phosphoryl) disulfide, as well as hydrolyzed dtp have also been detected on the sphalerite surface. The CSA parameters daniso and h are simulated with a Mathematica program and the principal values of the chemical shift tensor, dxx, dyy and dzz, have been calculated for the different compounds. Ligands of the same type have the same type of chemical shift tensor.

  • 19.
    Larsson, Anna-Carin
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Ivanov, Alexander V.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Forsling, Willis
    Nuclear magnetic resonance spectroscopy studies of mineral surfaces: application in the froth flotation2005In: Centenary of Flotation Symposium Proceedings, The Australian Institute of Mining and Metallurgy , 2005, p. 497-505Conference paper (Refereed)
    Abstract [en]

    Polycrystalline and surface complexes (at synthetic sphalerite, ZnS, and galena, PbS) of zinc(II) and lead(II) ions with eight different O,O'-dialkyldithiophosphate (Dtph) substances have been prepared and comparatively studied by means of 31P CP/MAS NMR spectroscopy. The 31P resonances have been assigned to dithiophosphate groups with terminal S,S'-chelating or bridging coordinations in the mono-, bi-. tetra- and polynuclear complexes respectively. The bridging coordination of two neighbouring zinc(II) ions by O,O '-dialkyldithio-phosphate ligands was established at the surface of synthetic sphalerite. The adsorption mechanism of dialkyldithiophosphate on synthetic galena includes formation of a surface complex as well as surface precipitation. Principally different coordination modes of the reagent were discovered at the surfaces of galena and sphalerite (ie terminal S,S'-chelating coordination to the lead atom). Derivatives of monothiophosphoric and phosphoric acids were displayed as hydrolysis products of dialkyldithiophosphates at synthetic PbS

  • 20.
    Larsson, Anna-Carin
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Hellström, Pär
    Fredriksson, Andreas
    Holmgren, Allan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Öberg, Sven
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Study of potassium O,O′-dibutyldithiophosphate combining DFT, 31P CP/MAS NMR and infrared spectroscopy2008In: Journal of Physical Chemistry A, ISSN 1089-5639, E-ISSN 1520-5215, Vol. 112, no 46, p. 11777-11783Article in journal (Refereed)
    Abstract [en]

    Dithiophosphates are used in many different industrial applications. To explain their functions and properties in these applications, a fundamental understanding on a molecular level is needed. Potassium O,O′-Dibutyldithiophosphate and its anion have been investigated by means of a combination of DFT and 31P CP/MAS NMR and infrared spectroscopy. Several low-energy conformations were studied by DFT. Three different conformations with significantly different torsion angles of the O-C bond relative to the O-P-O plane were selected for further studies of infrared frequencies and 31P NMR chemical-shift tensors. A good agreement between theoretical and experimental results was obtained, especially when the IR spectra or 31P chemical shift tensor parameters of all three conformations were added, indicating that, because of the low energy difference between the conformations, the molecules are rapidly fluctuating between them.

  • 21.
    Larsson, Anna-Carin
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Ivanov, Alexander V.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Forsling, Willis
    A 31P CP/MAS NMR study of PbS surface O,O′-dialkyldithiophosphate lead(II) complexes2008In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 327, no 2, p. 370-376Article in journal (Refereed)
    Abstract [en]

    31P CP/MAS NMR spectroscopy was used to study the adsorption of six different O,O′-dialkyldithiophosphate ions on the surface of synthetic galena (PbS). The 31P CP/MAS NMR spectra of the surface lead(II) dithiophosphates were compared with the 31P CP/MAS NMR spectra of polycrystalline lead(II) dithiophosphate complexes of the same ligands. Surface complexation of the dialkyldithiophosphate ions was established on the surface of PbS. A terminal S,S′-chelating coordination is suggested for the surface complexes. The bulkier alkyl groups lead to surface precipitation in addition to the surface adsorption. Derivatives of monothiophosphoric and phosphoric acids were displayed as hydrolysis products of dialkyldithiophosphates on the synthetic PbS, the amount of which depends on the type of alkyl group.

  • 22.
    Larsson, Anna-Carin
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Ivanov, Alexander V.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Gerasimenko, Andrey V.
    Far Eastern Branch of the Russian Academy of Sciences, Vladivostok.
    Forsling, Willis
    Complexation of lead(II) with O,O′-dialkyldithiophosphate ligands: 31P and 13C CP/MAS NMR and single-crystal X-ray diffraction studies2004In: Inorganica Chimica Acta, ISSN 0020-1693, E-ISSN 1873-3255, Vol. 357, no 9, p. 2510-2518Article in journal (Refereed)
    Abstract [en]

    Polycrystalline lead(II) complexes with O,O′-dipropyl- and O,O′-di-cyclo-hexyldithiophosphate ions were prepared and studied by means of 31P, 31C CP/MAS NMR spectroscopy and single-crystal X-ray diffraction. Prepared complexes are characterised by polynuclear structures, in which pairs of dithiophosphate groups asymmetrically link neighbouring lead atoms, forming infinite linear zigzag chains. In spite of the same combined structural function, dithiophosphate ligands in both complexes display structural inequivalence. To characterise the combined structural state of the dialkyldithiophosphate ligands, 31P chemical shift anisotropy parameters, δaniso and η, were estimated from spinning sideband patterns in experimental CP/MAS NMR spectra for each of the two prepared complexes as well as the initial potassium O,O′-dipropyl- and O,O′-di-cyclo-hexyldithiophosphate salts.

  • 23.
    Larsson, Anna-Carin
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Ivanov, Alexander V.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Forsling, Willis
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Abraham, Anu
    Georgetown University.
    Dios, Angel de
    Georgetown University.
    Correlations between 31P Chemical Shift Anisotropy and Molecular Structure in Polycrystalline O,O'-Dialkyldithiophosphate Zinc(II) and Nickel(II) Complexes: 31P CP/MAS NMR and Ab Initio Quantum Mechanical Calculation Studies2005In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 127, no 7, p. 2218-2230Article in journal (Refereed)
    Abstract [en]

    Different potassium salts and zinc(II) and nickel(II) O,O'-dialkyldithiophosphate complexes were studied by solid-state 31P CP/MAS and static NMR and ab initio quantum mechanical calculations. Spectra were obtained at different spinning frequencies, and the intensities of the spinning sidebands were used to estimate the chemical shift anisotropy parameters. Useful correlations between the shapes of the 31P chemical shift tensor and the type of ligand were found: terminal ligands have negative values of the skew , while bridging and ionic ligands have positive values for this parameter. The experimental results were compared with known X-ray diffraction structures for some of these complexes as well as with ab initio quantum mechanical calculations, and a useful correlation between the δ22 component of the 31P chemical shift tensor and the S-P-S bond angle in the O,O'-dialkyldithiophoshate zinc(II) and nickel(II) complexes was found: δ22 increases more than 50 ppm with the increase of S-P-S bond angle from ca. 100 to 120, while the other two principal values of the tensor, δ11 and δ33, are almost conserved. This eventually leads to the change in sign for in the bridging type of ligand, which generally has a larger S-P-S bond angle than the terminally bound O,O'-dialkyldithiophoshate group forming chelating four-membered P<>Me heterocycles

  • 24.
    Larsson, Anna-Carin
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Ivanov, Alexander V.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Pike, Kevin J.
    Materials and Engineering Science, ANSTO.
    Forsling, Willis
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Solid state 31P and 207Pb MAS NMR studies on polycrystalline O,O′-dialkyldithiophosphate lead(II) complexes2005In: Journal of magnetic resonance, ISSN 1090-7807, E-ISSN 1096-0856, Vol. 177, no 1, p. 56-66Article in journal (Refereed)
    Abstract [en]

    A number of lead(II) O,O′-dialkyldithiophosphate complexes were studied by 13C, 31P, and 207Pb MAS NMR. Simulations of 31P chemical shift anisotropy using spinning sideband analysis reveal a linear relationship between the SPS bond angle and the principal values δ22 and δ33 of the 31P chemical shift tensor. The 31P CSA data were used to assign ligands with different structural functions. In the cases of Adiethyldithiophosphate and di-iso-butyldithiophosphate lead(II) complexes, 2J (31P, 207Pb)-couplings were resolved and used to confirm the suggested assignment of the ligands. The SIMPSON computer program was used to calculate 31P and 207Pb spectral sideband patterns.

  • 25.
    Larsson, Anna-Carin
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Ivanov, Maxim A.
    Institute of Geology and Nature Management, Far East Branch, Russian Academy of Sciences, Blagoveshchensk.
    Gerasimenko, Andrey V.
    Institute of Chemistry, Far Eastern Branch of the Russian Academy of Sciences, 690022, Vladivostok.
    Ivanov, Alexander V.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Synthesis of four different antimony(III) O,O’-dialkyldithiophosphates: characterization by 31P CP/MAS NMR, single crystal X-ray diffraction, and adsorption at a stibnite surface (Sb2S3)2012In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 368, no 1, p. 488-495Article in journal (Refereed)
    Abstract [en]

    Four different dialkyldithiophosphate (DTP) ions, (RO)2PSS– (R = C3H7, iso-C3H7, iso-C4H9, cyclo-C6H11) have been adsorbed on the surface of synthetically prepared stibnite, Sb2S3, and studied by means of 31P CP/MAS NMR. Corresponding individual [Sb{(S2P(OR)2}3] complexes have also been synthesized and used for comparison with the surface adsorbed DTP species. The results show that a low concentration of collector at the surface leads to a chemisorbed monolayer of DTP on the mineral surface. At high concentration of DTP, a surface precipitate of Sb(DTP)3 is formed. 31P CP/MAS NMR and chemical shift anisotropy data indicate that the S–P–S bite angle of the chemisorbed DTP groups on the surface is larger than in the corresponding precipitated complexes and the coordination of the ligands differ. Using single-crystal X-ray diffraction technique, the molecular structure of a solvated form of crystalline O,O’-di-cyclo-hexyldithiophosphate antimony(III) complex has been resolved. In this novel molecular structure, the central antimony atom S,S’-anisobidentately coordinates three structurally non-equivalent DTP groups and, therefore, the geometry of the [SbS6] chromophore can be approximated by a distorted octahedron. Besides that, useful correlations between 31P CSA parameters and structural data on this complex were also established.

  • 26.
    Larsson, Anna-Carin
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Öberg, Sven
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Mathematical Science.
    Study on potassium iso-propylxanthate and its decomposition products: experimental 13C CP/MAS NMR combined with DFT calculations2011In: Journal of Physical Chemistry A, ISSN 1089-5639, E-ISSN 1520-5215, Vol. 115, no 8, p. 1396-1407Article in journal (Refereed)
  • 27.
    Nooshabadi, Alireza Javadi
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Kota, Hanumantha Rao
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Sustainable Process Engineering.
    Formation of hydrogen peroxide by pyrite and its influence on flotation2013In: Minerals Engineering, ISSN 0892-6875, E-ISSN 1872-9444, Vol. 49, p. 128-134Article in journal (Refereed)
    Abstract [en]

    Formation of hydrogen peroxide (H2O2), an oxidizing agent stronger than oxygen, by pyrite (FeS2), the most abundant metal sulphide on Earth, during grinding was investigated. It was found that pyrite generated H2O2 in pulp liquid during wet grinding and also the solids when placed in water immediately after dry grinding. Type of grinding medium on formation of hydrogen peroxide revealed that the mild steel produced more H2O2 than stainless steel grinding medium, where Fe2+ and/or Fe3+ ions played a key role in producing higher amounts of H2O2. The effect of grinding atmosphere of air and N2 gas showed that nitrogen environment free from oxygen generated more H2O2 than air atmosphere suggesting that the oxygen in hydrogen peroxide is derived from water molecules. In addition, the solids after dry grinding producing more H2O2 than wet grinding indicate the role of pyrite surface or its catalytic activity in producing H2O2 from water. This study highlights the necessity of relooking into the electrochemical and/or galvanic interaction mechanisms between the grinding medium and pyrite in terms of its flotation behaviour.

  • 28.
    Patra, Anuttam
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Taner, Hasan Ali
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering. Department of Mining Engineering, Selcuk University Konya Turkey.
    Bordes, R.
    Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Göteborg.
    Holmberg, K.
    Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Göteborg.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Selective flotation of calcium minerals using double-headed collectors2019In: Journal of Dispersion Science and Technology, ISSN 0193-2691, E-ISSN 1532-2351, Vol. 40, no 8, p. 1205-1216Article in journal (Refereed)
    Abstract [en]

    A study was performed involving a series of double-headed carboxylate collectors with varying distance between the head groups (one, two or three carbon atoms). A collector with the same alkyl chain length but with only one carboxylate group was also included. All these were amino-acid based amphiphiles and the polar head group was connected to the hydrophobic tail via an amide linkage. Selective flotation recovery of different calcium minerals using these collectors was investigated. The double-headed collector with one carbon atom between the carboxylate groups was an apatite and fluorite specific reagent while the monocarboxylate surfactant showed high specificity for calcite. The flotation behavior of a simple conventional collector of the same alkyl chain length, a fatty acid salt, was also determined under identical flotation conditions in order to understand the effect of the amide group. Complementary experiments (ζ potential measurements, adsorption isotherm determinations) were also performed for these reagents. In order to shed light on the selectivity obtained with the dicarboxylate surfactants, the distances between the head groups were calculated and compared with the distances between neighboring calcium atoms on the surface of the minerals. It was found that the high degree of selectivity could be rationalized by perfect matching of these distances. To the best of our knowledge this is the first study where flotation selectivity in complex calcium mineral systems has been explained in terms of molecular recognition governing the interaction between the collector and the mineral surface.

  • 29.
    Ruyter-Hooley, Maika
    et al.
    La Trobe University.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Johnson, Bruce B.
    La Trobe University.
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Angove, Michael J.
    La Trobe University.
    Surface complexation modeling of inositol hexaphosphate sorption onto gibbsite2015In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 440, p. 282-291Article in journal (Refereed)
    Abstract [en]

    The sorption of Inositol hexaphosphate (IP6) onto gibbsite was investigated using a combination of adsorption experiments, 31P solid-state MAS NMR spectroscopy, and surface complexation modelling. Adsorption experiments conducted at four temperatures showed that IP6 sorption decreased with increasing pH. At pH 6, IP6 sorption increased with increasing temperature, while at pH 10 sorption decreased as the temperature was raised. 31P MAS NMR measurements at pH 3, 6, 9 and 11 produced spectra with broad resonance lines that could be de-convoluted with up to five resonances (+5, 0, -6, -13 and -21 ppm). The chemical shifts suggest the sorption process involves a combination of both outer- and inner-sphere complexation and surface precipitation. Relative intensities of the observed resonances indicate that outer-sphere complexation is important in the sorption process at higher pH, while inner-sphere complexation and surface precipitation are dominant at lower pH. Using the adsorption and 31P MAS NMR data, IP6 sorption to gibbsite was modelled with an Extended Constant Capacitance Model (ECCM). The adsorption reactions that best described the sorption of IP6 to gibbsite included two inner-sphere surface complexes and one outer-sphere complex:

  • 30.
    Ruyter-Hooley, Maika
    et al.
    La Trobe University.
    Larsson, Anna-Carin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Johnson, Bruce B.
    La Trobe University.
    Antzutkin, Oleg
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Chemical Engineering.
    Angove, Michael J.
    La Trobe University.
    The effect of inositol hexaphosphate on cadmium sorption to gibbsite2016In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 474, p. 159-170Article in journal (Refereed)
    Abstract [en]

    HypothesisOxides, hydrous oxides and hydroxides of aluminium and iron are important in determining the availability of trace and heavy metals in soil systems. The presence of complexing anions is also known to affect the binding of these metals in soils. Since organophosphates, such as inositol hexaphosphate (IP6), are present in most soil systems they are expected to affect the nature of the interaction between metal ions and metal (hyr)oxides.ExperimentsBoth adsorption edge and isotherm experiments were conducted on Cd(II)–gibbsite and Cd(II)–IP6–gibbsite systems. In addition, solid-state 31P MAS NMR measurements were performed on the ternary system. All results were used to develop Extended Constant Capacitance surface complexation models of both the Cd(II)–gibbsite and IP6–Cd(II)–gibbsite sorption systems.FindingsThe presence of IP6 significantly increased sorption of Cd(II) to gibbsite below pH 8 especially at higher concentrations of Cd(II) and IP6. The 31P MAS NMR spectra, together with surface complexation modeling, indicated the presence of two outer-sphere ternary complexes with the first, [(SOH2)33+–(LHCd)9-]6-, important at relatively low concentrations, while the second, [SLH38-−Cd2+]6-, dominated sorption at higher sorbate concentrations. Thus the presence of organophosphates in soil systems increases sorption and may therefore decrease the availability of trace and heavy metals to plants.

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