Mixed-Ligand Complexes of Ni(i-Bu2PS2)2 with 4-Aminopyridine. Structure of [Ni(4-NH2Py)(i-Bu2PS2)2]

Mixed-ligand complexes [Ni(4-NH₂Py) (i-Bu₂PS₂)₂] (I) and Ni(4-NH₂Py)₂(i-Bu₂PS₂)₂ (II) have been synthesized. Single crystals were grown and X-ray diffraction data (CAD-4 diffractometer, Mo_{K α} radiation, 1477 F _hkl , R = 0.0320) were used to determine the structure of I. The crystals are orthorhombic: a = 10.675(1) Å; b = 21.681(2) Å; c = 26.302(4) Å, V = 6087.5(12) ų, Z = 8, ρ(calc) = 1.247 g/cm³, space group Pbca. Complex I possesses a mononuclear molecular structure. The coordination polyhedron of the Ni atom is a tetragonal pyramid NS₄ whose base is formed by four S atoms of two cyclic bidentate ligands i-Bu₂PS ₂ ⁻ and the axial position is occupied by the N atom of the 4-NH₂Py cycle. According to electron spectroscopy data, complex II has an octahedral N₂S₄ environment of the Ni atom.Original Russian Text Copyright © 2004 by T. E. Kokina, L. A. Glinskaya, E. A. Novoselova, R. F. Klevtsova, and S. V. Larionov__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 5, pp. 899–904, September–October, 2004.     

Synthesis of Cu(II) complexes containing 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene (L) and diisobutyldithiophosphinate or isobutylxanthate. Crystal Structure of [CuL](iso-Bu2PS2)2

The reaction of Cu(II) complex with 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotet-radeca-4,11-diene (L) and iso-Bu₂PS₂⁻ or iso-BuOCS₂⁻ anions gave stable paramagnetic compounds [CuL](iso-Bu₂PS₂)₂ (I) (μ_eff = 1.77 μB) and [CuL](iso-BuOCS₂)₂ (II) (μ_eff = 1.76 μB). According to X-ray diffraction, the crystal structure of I is composed of discrete centrosymmetric complex cations [CuL]²⁺ and iso-Bu₂Ps₂⁻ anions. The CuN₄ coordination unit is a square. The Cu...S distance (iso-Bu₂PS₂⁻) equal to 3.047 ? attests to possible S-coordination. Compounds I and II were studied by EPR.     

Crystal and molecular structures of Ni[(iso-C4H9)2PS2]2 and Pd[(iso-C4H9)2PS2]2 chelates

Crystal structures of chelate compounds Ni[(iso-C₄H₉)₂PS₂]₂ (I) and Pd[(iso-C₄H₉)₂PS₂]₂ (II) have been determined by X-ray diffraction: diffractometer X8-APEX, MoK _α∔ -radiation, 1048 F _hkl , R = 0.0544 for I and CAD-4 diffractometer, MoK _α∔ -radiation, 1283 F _hkl , R = 0.0347 for II. The crystals are rhombic: a = 12.921(5) Å, b = 17.094(5) Å, c = 22.971(5) Å; V = 5074(3) ų, Z = 8, calc = 1.250 g/cm³, space group Pbca for I and a = 13.312(3) Å, b = 16.130(7) Å, c = 23.171(5) Å; V = 4975(3) ų, Z = 8, ρ_calc = 1. 208 g/cm³, space group Pbca for II. The structures of I and II are formed by discrete mononuclear molecules. Coordination cores MS₄ (M = Ni, Pd) approach planar square configurations. Original Russian Text Copyright ? 2005 by L. A. Glinskaya, T. G. Leonova, T. E. Kokina, R. F. Klevtsova, and S. V. Larionov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 46, No. 4, pp. 715–720, July–August, 2005.     

Synthesis of heteroligand complex Nd(Phen){( iso -C4H9)2PS2}2(NO3). Crystal structure of [Nd(Phen){( iso -C4H9)2PS2}3] and luminescent properties of these compounds

The heteroligand complex Nd(Phen){(iso-C₄H₉)₂PS₂}₂(NO₃) (I) was synthesized and its IR spectrum was analyzed. The anions (iso-C₄H₉)₂PS_2/− and N_3/− act as bidentate cyclic ligands. The single crystals of [Nd(Phen){iso-C₄H₉)₂PS₂}₃] (II) were obtained on evaporation of a solution of complex I in a mixture CH₂Cl₂-hexane and were studied by X-ray diffraction. Crystals II are triclinic: a = 10.5509(5); b = 14.7432(8), c = 16.8503(10) ?; α = 102.882(2)°, β = 97.211(2)°, γ= 108.087(2)°, V = 2374(2) ?³, Z = 2, ρ(calcd.) = 1.332 g/cm³, space group . The coordination polyhedron of the Nd atom in a separate mononuclear molecule II is a distorted dodecahedron N₂S₆. The molecules are bound by weak van der Waals and π-π interactions. The photoluminescence spectra of complexes I, II were measured and interpreted. Original Russian Text ? S.V. Larionov, V.L. Varand, R.F. Klevtsova, T.G. Leonova, L.A. Glinskaya, E.M. Uskov, 2008, published in Koordinatsionnaya Khimiya, 2008, Vol. 34, No. 12, pp. 944–950.     

Crystal and molecular structures of the Rh[(C2H5O)2PS2]3 and Co[(C6H5O)2PS2]3 chelate compounds

The crystal structures of the Rh[(EtO)₂PS₂]₃ (I) and Co[(PhO)₂PS₂]₃ (II) chelate compounds were determined from X-ray diffraction (XRD) data (CAD-4 diffractometer, MoK _β radiation, 1193 F _hkl , R = 0.0516 for I and 513 F _hkl , R = 0.0305 for II). Crystals I are monoclinic: a = 14.233(3) Å, b = 13.570(3) Å, c = 14.272(3) Å; β = 90.66(3)°, V = 2756.3(10) ų, Z = 4, ρ_calc = 1.587 g/cm³, space group C2/c. Crystals II are trigonal: a = 15.149(2) Å, c = 30.306(6) Å; V = 6023.2(16) ų, Z = 6, ρ_calc = 1.493 g/cm³, space group R3ˉ. Structures I and II consist of discrete mononuclear molecules. The coordination polyhedra of the M atoms (M = Rh, Co) are distorted octahedra formed by six sulfur atoms of three cyclic bidentate (RO)₂ PS₂⁻ ligands. Original Russian Text Copyright ? 2008 by R. F. Klevtsova, L. A. Glinskaya, and S. V. Larionov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 2, pp. 330–334, March–April, 2008.     

Crystal and molecular structure of the [Y(Phen){( i -C4H9)2PS2}2NO3] mixed-ligand compound

The [Y(Phen){(i-C₄H₉)₂PS₂}₂NO₃] mixed-ligand compound (I) was synthesized. Its structure was determined by X-ray diffraction analysis (X8 APEX diffractometer, λMoK _α , 3788 F _hkl , R = 0.0677). Crystals I are orthorhombic: a = 10.6495(8) Å, b = 20.006(2) Å, c = 35.317(4) Å, V = 7524.4(13) ų, Z = 8, ρ_calc = 1.324 g/cm³, space group Pbca. The structure is built of mononuclear discrete molecules. The N₂O₂S₄ coordination polyhedron of the Y atom is a distorted dodecahedron. Original Russian Text Copyright ? 2008 by V. L. Varand, L. A. Glinskaya, R. F. Klevtsova, and S. V. Larionov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 1, pp. 182–186, January–February, 2008.     

Synthesis and crystal and molecular structure of CdPhen( iso -C4H9OCS2)2 and CdPhen( n -C4H9OCS2)2 mixed-ligand complexes

Mixed-ligand complexes CdPhen(i-BuOCS₂)₂ (I) and CdPhen(n-BuOCS₂)₂ (II) have been synthesized. Their structures were solved using X-ray diffraction data (X8 APEX diffractometer, MoK _α radiation, 1641 and 2497 F _hkl , R = 0.0359 and 0.0389). Crystals I are orthorhombic with unit cell parameters a = 6.5883(3) Å, b = 19.7123(10) Å, c = 20.1936(11) Å, V = 2622.6(2) ų; Z = 4, space group Pbcn; crystals II are monoclinic, a = 6.5845(2) Å, b = 19.1522(6) Å, c = 20.7091(7) Å, β = 97.106(1), V = 2591.5(1) ų, Z = 4, space group C2/c. The structures consist of discrete mononuclear molecules in which the coordination polyhedron of the Cd atom is a distorted N₂S₄ octahedron. Molecular packing and interactions in the structures are discussed. Original Russian Text Copyright ? 2007 by R. F. Klevtsova, T. G. Leonova, L. A. Glinskaya, and S. V. Larionov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 48, No. 2, pp. 274–281, March–April, 2007.     

Crystal and molecular structure of (NH4)2[UO2(NO3)4] and [(NH4)(18C6)]2[UO2(NO3)4]

Single crystals of diammonium tetranitratouranylate (NH₄)₂[UO₂(NO₃)₄] (I) and a new diammonium tetranitratouranylate complex with 18-crown-6 [(NH₄)(18C6)]₂[UO₂(NO₃)₄] (II) have been synthesized by the reaction of diaquadinitratouranyl tetrahydrate with ammonium nitrate in a nitric acid solution and the reaction of the same reagents with 18C6 in an ethanol solution, respectively. The X-ray diffraction analysis of compounds I and II has been performed. Crystals of compounds I and II are monoclinic, Z = 2, space group P2₁/n, a = 6.4075(5) ?, b = 7.7851(7) ?, c = 12.4461(12) ?, β = 101.239(1)°, V = 608. 94(9) ?³ for compound I and a = 10.542(9) ?, b = 8.590(8) ?, c = 22.5019(19) ?, β = 101.632(1)°, V = 2058.3(3) ?³ for compound II. The [UO₂(NO₃)₄]²⁻ complex anion in compounds I and II contains two monodentate and two bidentate cyclic nitrato groups, and the coordination number of uranyl is 6. The 18C6 molecule in the structure of compound II has the classic crown conformation and combined with the ammonium ion by three hydrogen bonds. Compounds I and II formed by electrostatic attraction forces between counterions are stabilized by (NH₄⁺)NH...O(NO₃⁻) interionic hydrogen bonds.     

Synthesis and characterization of the [Cu(Cin2bda)2]ClO4 and [Cu(Ncin2bda)2]ClO4 complexes: Crystal structure of [Cu(Ncin2bda)2]ClO4

Two copper(I) complexes [Cu(Cin₂bda)₂]ClO₄ (I) and [Cu(Ncin₂bda)₂]ClO₄ (II) have been prepared by the reaction of the ligands N²,N²′-bis(3-phenylallylidene)biphenyl-2,2′-diamine (L¹) and N²,N²′-bis[3-(2-nitrophenyl)allylidene]biphenyl-2,2′-diamine (L²) and copper(I) salt. These compounds were characterized by CHN analyses, ¹H NMR, IR, and UV-Vis spectroscopy. The C=N stretching frequency in the copper(I) complexes shows a shift to a lower frequency relative to the free ligand due to the coordination of the nitrogen atoms. The crystal and molecular structure of II was determined by X-ray single-crystal crystallography. The coordination polyhedron about the copper(I) center in the complex is best described as a distorted tetrahedron. A quasireversible redox behavior was observed for complexes I and II. The article is published in the original.     

Synthesis, structure, and properties of [RuNO(NH3)4OH][PtCl4] and [RuNO(NH3)4OH][PdCl4]

Double complex [RuNO(NH₃)₄OH][PtCl₄] (I) and [RuNO(NH₃)₄OH][PdCl₄] (II) salts have been prepared and explored with TGA, IR spectroscopy, powder and single crystals X-ray diffraction. Crystal phases of I and II are isostructural (space group Cmc2₁) and have the following crystal chemical characteristics: a = 8.106 Å, b = 18.190(3) Å, c = 8.097 Å, V = 1194.0 ų, Z = 4, ρ_calc = 3.077 g/cm³ (I), and a = 8.116 Å, b = 18.135 Å, c = 8.062 Å, V = 1186.5 ų, Z = 4, ρ_calc = 2.600 g/cm³ (II). The product of thermal decomposition of I in inert and hydrogen atmospheres is a substitution solid solution Pt_0.5Ru_0.5 with the parameter of the FCC unit cell a = 3.856(3) Å. Thermolysis of II affords two-phase mixtures of limited solid solutions of the metals featuring Ru-based HCP and Pd-based FCC cells. __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 48, No.1, pp.114–121, January–February, 2007.     

Structure and properties of double complex salts [Co(NH3)6][Fe(CN)6] and [Co(NH3)6]2[Cu(C2O4)2]3

Double complex salts (DCSs) [Co(NH₃)₆][Fe(CN)₆] (I) and [Co(NH₃)₆]₂[Cu(C₂O₄)₂]₃ (II) and complex [Co(NH₃)₆]₂(C₂O₄)₃·4H₂O (III) are synthesized and investigated by single crystal XRD, crystal optics, and elemental analysis. The crystalline phases of I, II, and III (R-3, P2₁/c, and Pnnm space groups respectively) have the following crystallographic characteristics: a = 10.9804(2) ?, b = 10.9804(2) ?, c = 10.8224(3) ?, V = 1130.03(4) ?³, Z = 3, d _x = 1.65 g/cm³ (I); a = 9.6370(2) ?, b = 10.2452(2) ?, c = 13.2108(3) ?, V = 1932.90(9) ?³, Z = 2, d _x= 1.97 g/cm³ (II), and a = 11.7658(3) ?, b = 11.7254(3) ?, c = 14.1913(4) ?, V = 1304.34(5) ?³, Z = 2, d _x = 1.68 g/cm³ (III). This paper investigates the products of DCS thermolysis in a hydrogen atmosphere: the intermetallic compound CoFe with the bcc parameter a = 2.852 ? for I and a heterogeneous mixture of Co and Cu in the decomposition of II. The coordinated CN⁻ and C₂O₄²⁻ groups then turn into NH₃, hydrocarbons, and CO₂. The dominant hydrocarbon is methane.     

Synthesis and crystal and molecular structure of mixed-ligand complexes Cd(2,2′-Bipy)(i-PrOCS2)2 and (2,2′-Bipy)(i-BuOCS2)2

Mixed-ligand complexes Cd(2,2′-Bipy)(i-PrOCS₂)₂ (I) and Cd(2,2′-Bipy)(i-BuOCS₂)₂ (II) have been prepared. Their structures were solved using the X-ray diffraction technique (X8 APEX diffractometer, MoK _α radiation, 1941 and 4244 F _hkl , R = 0.0188 and 0.0379). The crystals are orthorhombic with unit cell parameters a = 18.1404(4) Å, b = 6.9513(1) Å, c = 17.5835(4) Å; V = 2217.27(8) ų, Z = 4, space group Pccn (for complex I) and a = 11.7890(3) Å, b = 12.1859(3) Å, c = 17.5335(5) Å; V = 2518.9(1) ų, Z = 4, space group P2₁2₁2₁ (for complex II). The structures consist of isolated mononuclear molecules. The cadmium atoms have distorted octahedral N₂S₄ environments. Molecular packings and intermolecular interactions in the structures are considered. __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 46, No. 6, pp.1064–1071, November–December, 2005. Original Russian Text Copyright ? 2005 by S. V. Larionov, L. A. Glinskaya, T. G. Leonova, and R. F. Klevtsova     

Monomeric [Ni(2,2"-Bipy){(i-C4H9)2PS2}2] and [Ni(Pz)2{(i-C4H9)2PS2}2] and Polymeric [Ni(Pz){(i-C4H9)2PS2}2]nComplexes (Pz = Pyrazine): Synthesis,Structures, and Properties

Diamagnetic [Ni(i-Bu₂PS₂)₂] compound (I) in ethanol reacts with 2,2"-bipyridine or pyrazine to give the paramagnetic complexes [Ni(2,2"-Bipy)(i-Bu₂PS₂)₂] (II), [Ni(Pz)₂(i-Bu₂PS₂)₂] (III), and [Ni(Pz)(i-Bu₂PS₂)₂] _n (IV) (_eff= 2.91–3.12 _B). Single crystals of IIwere grown for X-ray diffraction study. The crystals are monoclinic, a= 14.669(3) Å, b= 19.693(4) Å, c= 12.155(2) Å, = 107.51(3)°, V= 3348(1) ų, Z= 4; _calcd= 1.257 g/cm³, space group P2₁/c. The structure is built from monomeric molecules. The coordination polyhedron of the Ni atom is a distorted octahedron formed by four S atoms of two bidentate chelating i-Bu₂PS^– ₂ligands and by two N atoms of bidentate cyclic 2,2"-Bipy. Preliminary data for complexes IIIand IVindicate that they also contain an octahedral NiN₂S₄fragment. The structures of complexes I(square planar) and ofII–IV(octahedral) were confirmed by data from electron spectroscopy. Electronic absorption spectra were used to determine the rankings of the i-Bu₂PS^– ₂ions and Pz on a spectrochemical scale.     

Crystal structure of ansa-Me2Si-(2Me-4-p-Tol-cyclopenta[b]indol-3-yl)2ZrCl2 and its catalytic properties in the polymerization of propylene

A new zirconocene ansa-Me₂Si-(2Me-4-p-Tol-cyclopenta[b]indol-3-yl)₂ZrCl₂ complex (I), in which the Cp ligand is fused with the indole ring, has been synthesized and studied by X-ray diffraction analysis. Light brown crystals are triclinic, space group P [`1]\bar 1; M = 734.92, a = 9.252(2) ?, b = 12.914(3) ?, c = 15.619(3) ?, α = 111.83(3)°, β = 81.03(3)°, γ = 117.77(3)°, V = 1569(3) ?³, Z = 2, ρ_calc = 1.525 g/cm³. The structural parameters of complex I are compared with the known bis-indenyl zirconium complexes: rac-Me₂Si(Ind)₂ZrCl₂ (II) and rac-Me₂Si(2Me-2Ph-1-Ind)₂ZrCl₂ (III) and analogous substituted rac-Me₂Si(2,5-Me₂-3Ph-6-Cp[b]Tp)₂ZrCl₂ (IV) and rac-Me₂Si(2,5-Me₂-1Ph-4-Cp[b]Py)₂ZrCl₂ (V). Complex I alkylated by the Grignard reagent (MgMe₂) in the presence of the Al-iso-Bu₃ cocatalyst is an efficient catalyst for the polymerization of propylene into isotactic polypropylene.     

Nickel(II) Diisobutyldithiophosphinate Complexes with Hexamethylenetetramine and Triethylenediamine: Synthesis and Properties. Crystal and Molecular Structure of [Ni2(C6H12N4){(i-C4H9)2PS2}4]

The paramagnetic compounds [Ni₂(HMTA)(i-Bu₂PS₂)₄] (I) and [Ni₂(TEDA)(i-Bu₂PS₂)₄] (II) (_eff = 3.11 and 3.23 _B, respectively) were synthesized by reacting diamagnetic Ni(i-Bu₂PS₂)₂ with hexamethylenetetramine (HMTA) and triethylenediamine (TEDA) in ethanol. The crystal structure of I was established by single-crystal X-ray diffraction analysis (CAD4 diffractometer, MoK radiation, 1483 F _hkl, R = 0.0648). The crystals are monoclinic: a = 35.212(7) Å, b = 9.313(2) Å, c = 22.622(5) Å; = 129.97(3)°, V = 5685(2) ų, Z = 4, (calcd) = 1.281 g/cm³, space group C2/c. The structure is built of discrete binuclear molecules. The coordination polyhedron of the Ni atom is a distorted tetragonal pyramid with four S atoms of two bidentate cyclic ligands i-Bu₂PS₂ ^– in the base and the N atom of the bidentate bridging ligand HMTA at the axial vertex. Complexes I and II have similar electronic reflection spectra, which agrees with the C _4v symmetry of the ligand field.     

Tetrahedral complexes of zinc(II) chloride with N- and O-containing organic ligands: Synthesis and crystal structures of [ZnCl2(C12H12N2O)] and [ZnCl2(H2O)2](Me4Pyz)2

New complex chlorides [ZnCl₂(ODA)] (I) (ODA=oxydianiline, C₁₂H₁₂N₂O) and [ZnCl₂(H₂O)₂](Me₄Pyz)₂ (II) (Me₄Pyz = 2,3,5,6-tetramethylpyrazine) were synthesized and crystallographically characterized. Crystals of I are monoclinic, space group C2/c, a = 22.682(2) ?, b = 12.646(1) ?, c = 9.951(1) ?, β = 93.23(2)°, V = 2849.7(5) ?³, ρ_calc = 1.569 g/cm³, Z = 8. Structure I contains cyclic fragments consisting of two tetrahedral complexes (ZnCl₂N₂) and two coordinated bridging oxydianiline ligands. Crystals of II are monoclinic, space group P2(1)/c, a = 8.972(2) ?, b = 13.862(3) ?, c = 17.528(4) ?, β = 101.72(3)°, V = 2134.5(7) ?³, ρ_calc = 1.384 g/cm³, Z = 4. In structure II, supramolecular pseudo-metallocycles are formed due to formation of hydrogen bonds O(w)-H…N between coordinated water molecules and noncoordinated nitrogen atoms of tetramethylpyrazine molecules.     

One-and two-dimensional silver-tetramethylpyrazine coordination polymers with uncoordinated anions: Synthesis and structure of [Ag(Me4Pyz)]PF6 and [Ag2(Me4Pyz)3](BF4)2·H2O

Coordination polymers [Ag(Me₄Pyz)] PF₆(I) and [Ag₂(Me₄Pyz)₃](BF₄)₂·H₂O (II) have been synthesized, and their structures have been determined. The crystals of I are monoclinic, space group C2/c, a = 9.440(2) ?, b = 10.587(2) ?, c = 13.165(3) ?, β= 107.19(3)°, V = 1257.0(5) ?³, d = 2.056 g/cm³, Z = 4. The crystals of II are monoclinic, space group P2₁/n, a = 13.062(3) ?, b = 12.259(2) ?, c = 18.996(4) ?, β = 97.73(3)°, V = 3014.1(11)?³, ρ = 1.798 g/cm³, Z = 4. The structure of I is built of linear polymeric cations [Ag(C₈H₁₂N₂)] _∞ ⁺ and octahedral anions [PF₆]⁻. Upon the interaction of tetramethylpyrazine molecule with Ag⁺ ions, intersecting polymeric chains [Ag(C₈H₁₂)] _∞ ⁺ (1D polymer) are formed extending in mutually perpendicular diagonal directions. The structure of II consists of layers (2D polymers) formed by fused sixmembered rings. These rings consist of Ag⁺ ions linked by bridging ligands Me₄Pyz. Original Russian Text ? Yu.V. Kokunov, Yu.E. Gorbunova, 2007, published in Zhurnal Neorganicheskoi Khimii, 2007, Vol. 52, No. 5, pp. 743–750.     

Crystal structure of cadmium iodide complexes with acetamide and propaneamide [Cd(CH3CONH2)6][Cd2I6] and [Cd(C2H5CONH2)6][Cd2I6]

The complexes of CdI₂ with acetamide (AA) and propaneamide (PrA) of the composition [Cd(AA)₆][Cd₂I₆] (I) and [Cd(PrA)₆][Cd₂I₆] (II) were synthesized and studied by X-ray diffraction. Isostructural crystals I and II are triclinic: a = 7.285(3) and 8.066(6), b = 11.266(4) and 11.649(3), c = 11.554(3) and 12.063(2) ?, α = 100.96(2)° and 102.74(2)°, β = 91.59(2)° and 91.73(4)°, γ = 100.76(3)° and 101.05(4)°, V = 912.5 and 1081.9 ?³, respectively; space group , Z = 1. Original Russian Text ? I.A. Zamilatskov, E.V. Savinkina, D.V. Al’bov, 2007, published in Koordinatsionnaya Khimiya, 2007, Vol. 33, No. 6, pp. 407–410.     

Heterometallic clusters with the {MoNbI8} core: The synthesis and crystal structures of (Ph4P)2[Mo5NbI8Cl6] and (4-MePyH)5[Mo5NbI8Cl6]Cl2

Heterometallic chloride complexes [Mo₅NbI₈Cl₆] ⁿ⁻ (n = 2, 3) are synthesized. The crystal structures of their salts are determined: for (Ph₄P)₂[Mo₅NbI₈Cl₆] (I), triclinic crystal system, spacegroup P [`1]\bar 1, a = 10.9886(6), b = 11.4604(5), c = 13.4343(7) ?, α = 66.124(2), β = 86.892(2), γ = 86.490(2)°, Z = 1, V = 1543.35(13) ?³; and for (4-MePyH)₅[Mo₅NbI₈Cl₆]Cl₂ (II), monoclinic crystal system, space group C2/m, a = 16.4937(4), b = 14.7335(3), c = 11.6534(3) ?, β = 99.8750(10)°, Z = 2, V = 2789.94(11) ? The geometric parameters of compounds I and II and the conditions for the formation of the complexes with the charges −2 and −3 are discussed.