| 1. |
- Ivanov, Alexander, et al.
(author)
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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) disulphide
- 2013
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In: Journal of Molecular Structure. - : Elsevier BV. - 0022-2860 .- 1872-8014. ; 1034, s. 152-161
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Journal article (peer-reviewed)abstract
- 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.
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| 2. |
- Ivanov, Alexander V., et al.
(author)
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Conformational isomerism of the binuclear N,N-pentamethylenedithiocarbamate cadmium(II) complex, [Cd2{S2CN(CH2)5}4] on multinuclear (15N, 113Cd) CP/MAS NMR and single-crystal X-ray diffraction data
- 2006
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In: Inorganica Chimica Acta. - : Elsevier BV. - 0020-1693 .- 1873-3255. ; 359:12, s. 3855-3864
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Journal article (peer-reviewed)abstract
- Crystalline N,N-cyclo-pentamethylenedithiocarbamate (PmDtc) cadmium(II) complex was prepared and studied by means of 15N, 113Cd CP/MAS NMR spectroscopy and single-crystal X-ray diffraction. The unit cell of the cadmium(II) compound comprises two centrosymmetric isomeric binuclear molecules [Cd2{S2CN(CH2)5}4], which display structural inequivalence in both 15N and 113Cd NMR and XRD data. There are pairs of the dithiocarbamate ligands exhibiting different structural functions in both isomeric molecules. Each of the terminal ligands is bidentately coordinated to the cadmium atom and forms a planar four-membered chelate ring [CdS2C]; whereas pairs of the tridentate bridging ligands combine two neighbouring cadmium atoms forming an extended eight-membered tricyclic moieties [Cd2S4C2], whose geometry can be approximated by a ‘chair' conformation. The structural states of cadmium atoms were characterised by almost axially symmetric 113Cd chemical shift tensors. All experimental 15N resonance lines were assigned to the nitrogen structural sites in both isomeric binuclear molecules.
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| 3. |
- Larsson, Anna-Carin, et al.
(author)
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Complexation of lead(II) with O,O′-dialkyldithiophosphate ligands: 31P and 13C CP/MAS NMR and single-crystal X-ray diffraction studies
- 2004
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In: Inorganica Chimica Acta. - : Elsevier BV. - 0020-1693 .- 1873-3255. ; 357:9, s. 2510-2518
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Journal article (peer-reviewed)abstract
- 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.
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| 4. |
- Rodina, Tatyana A., et al.
(author)
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A pyridine adduct of bis(di-iso-butyldithiocarbamato-S,S′)cadmium(II) : multinuclear (13C, 15N, 113Cd) CP/MAS NMR spectroscopy, crystal and molecular structure, and thermal behaviour
- 2011
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In: Inorganica Chimica Acta. - : Elsevier BV. - 0020-1693 .- 1873-3255. ; 368:1, s. 263-270
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Journal article (peer-reviewed)abstract
- Crystalline bis(N,N-di-iso-butyldithiocarbamato-S,S′)(pyridine)cadmium(II) – adduct 1 was prepared and studied by means of multinuclear 13C, 15N, 113Cd CP/MAS NMR spectroscopy, single-crystal X-ray diffraction and simultaneous thermal analysis (STA). In molecular structure 1, the cadmium atom coordinates with four sulphur atoms and one nitrogen atom of pyridine, forming a coordination polyhedron [CdS4N] whose geometry is an almost ideal tetragonal pyramidal (C4v). The coordinated py molecule is in the apical position, while two structurally non-equivalent di-iso-butyldithiocarbamate ligands, playing the same terminal S,S’-chelating function, define the basal plane. To characterise additionally the structural state of the cadmium atom in this five-fold coordination, 113Cd chemical shift anisotropy (CSA) parameters, δaniso and η, were calculated from experimental MAS NMR spectra that revealed an almost axially symmetric 113Cd chemical shift tensor. From a combination of TG and DSC measurements taken under an argon atmosphere, we found that the mass of adduct 1 is lost in two steps involving initial desorption of coordinated py molecules with subsequent thermal destruction of liberated cadmium(II) di-iso-butyldithiocarbamate, with yellow-orange, fine-powdered solid CdS as the final product.
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| 5. |
- Rodina, Tatyana A., et al.
(author)
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Crystalline O,O’-di-sec-butyl and O,O’-diethyl dithiophosphate platinum(II) complexes : Synthesis, 13C and 31P CP/MAS NMR, single crystal X-ray diffraction studies and thermal behaviour
- 2011
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In: Polyhedron. - : Elsevier BV. - 0277-5387 .- 1873-3719. ; 30:13, s. 2210-2217
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Journal article (peer-reviewed)abstract
- Crystalline bis(O,O’-di-sec-butyldithiophosphato)platinum(II) was prepared and studied by means of 31P, 13C CP/MAS NMR spectroscopy and single-crystal X-ray diffraction. The unit cell of the platinum(II) compound is comprised of one centrosymmetric mononuclear molecule [Pt{S2P(O-sec-C4H9)2}2], in which the dithiophosphate groups display structural equivalence in both 31P NMR and XRD data. A pair of the dithiophosphate ligands exhibit the same S,S’-bidentate chelating structural function and form two planar four-membered chelate rings, [PtS2P], in this molecule. The planar configuration of the [PtS4] chromophore in structure 1 is governed by the dsp2-hybrid state of platinum(II). The structural states of the dithiophosphate groups in two different samples of complex 1 (one crystallised from ethanol and the other one precipitated from an aqueous solution) are all characterised by almost rhombic 31P chemical shift tensors. The observed essential dispersion of the 31P NMR chemical shift is caused by a coexistence of six optical isomers of molecule 1. The thermal behaviour of this compound was studied by means of simultaneous thermal analysis (a combination of TG and DSC) under an argon atmosphere. The thermal behaviour shows that the mass of 1 is lost in three steps, involving successive thermal decompositions of the organic and inorganic parts of this compound with platinum(II) dithio-meta-phosphate and reduced metallic platinum as the intermediate and the final products, respectively.
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| 6. |
- Rodina, Tatyana A., et al.
(author)
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Fixation modes of gold(III) from solutions using cadmium(II) dithiocarbamates : Preparation, supramolecular structure and thermal behaviour of polynuclear and heteropolynuclear gold(III) complexes: bis(N,N-dialkyldithiocarbamato-S,S’)gold(III) polychlorometallates, [Au(S2CNR2)2]nX (n =1: X = [AuCl4]–; n = 2: X = [CdCl4]2–, [Cd2Cl6]2–)
- 2012
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In: Polyhedron. - : Elsevier BV. - 0277-5387 .- 1873-3719. ; 40:1, s. 53-64
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Journal article (peer-reviewed)abstract
- Four novel heteropolynuclear and polynuclear complexes of the general formulae [Au(S2CNR2)2]2X (X = [CdCl4]2-, R = CH3 (1); X = [Cd2Cl6]2-, R = C3H7 (2)) and [Au(S2CNR2)2][AuCl4] (R = iso-C3H7 (3); R = iso-C4H9 (4)) were prepared using heterogeneous reactions between appropriate freshly precipitated binuclear cadmium(II) dialkyl dithiocarbamates and AuCl3 in 2 M hydrochloric acid. The isolated complexes were studied by 13C CP/MAS NMR spectroscopy, single-crystal X-ray diffraction and simultaneous thermal analysis (STA) under an argon atmosphere. In all molecular structures (1–4), one of the gold atoms coordinates two dialkyl dithiocarbamate ligands in the S,S’-bidentate mode, forming a square-planar coordination polygon [AuS4], while the other gold atom (in 3 and 4) has four neighbouring chlorine atoms [AuCl4]. At the supramolecular level, compounds 1 and 2 comprise binuclear cations, [Au2{S2CN(CH3)2}4]2+ and polynuclear chains, ([Au{S2CN(C3H7)2}2]+)n in a combination with [CdCl4]2- and [Cd2Cl6]2- anions, respectively. Unexpected structural distinctions at the supramolecular level were discovered for the chemically related compounds 3 and 4. In these ionic complexes, there are either cationic trinuclear formations, {[Au{S2CN(iso-C3H7)2}2]2[AuCl4]}+, or polynuclear chains, ([Au{S2CN(iso-C4H9)2}2]+)n, both combined with [AuCl4]– anions, in the structural basis of compounds 3 and 4, respectively.
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| 7. |
- Zaeva, Anna S., et al.
(author)
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Dialkyldithiocarbamate platinum(II) complexes of [Pt(S2CNR2)2] (R = iso-C3H7, iso-C4H9) : Preparation, 13C CP-MAS NMR, molecular structure, supramolecular self-assembly and thermal behaviour
- 2020
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In: Polyhedron. - : Elsevier. - 0277-5387 .- 1873-3719. ; 175
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Journal article (peer-reviewed)abstract
- Two new dialkyldithiocarbamato platinum(II) complexes of [Pt(S2CNR)2], R = iso-C3H7 (1) and iso-C4H9 (2), have been prepared and characterised using 13C CP-MAS NMR. The crystal and molecular structures of the isolated compounds were established by single-crystal X-ray diffraction. The unit cell of 1 contains four centrosymmetric discrete molecules of [Pt{S2CN(iso-C3H7)2}2], of which the pairs are structurally inequivalent to each other (hereafter denoted as molecules 1a and 1b). At the supramolecular level, due to numerous intermolecular C–H···S hydrogen bonds, the 1a molecules form linear polymeric ribbons, whose interaction with the 1b molecules results in a two-dimensional polymeric network. In the structure of 2, the construction of supramolecular zigzag chains by non-centrosymmetric molecules of [Pt{S2CN(iso-C4H9)2}2] is determined by intermolecular C–H···Pt anagostic interactions. The thermal behaviour of crystalline compounds 1 and 2 was studied by simultaneous thermal analysis (STA), a combination of the TG and DSC techniques, under an argon atmosphere. In both cases, platinum(II) sulphide (PtS) was identified as the main end-product upon thermal decomposition of the complexes at 600 °C.
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