Synthesis and structure of the platinum complexes [Bu4N]+[PtBr5(DMSO)]?, [Ph4P]+[PtBr5(DMSO)]?, and [Ph3(n-Am)P]+[PtBr5(DMSO)]?

The complexes [Bu₄N]₂⁺[PtBr₆]²⁻ (I), [Ph₄P]₂⁺[PtBr₆]²⁻ (II), and [Ph₃(n-Am)P]₂⁺ (III) are synthesized by the reactions of tetrabutylammonium bromide, tetraphenylphosphonium bromide, and triphenyl(n-amyl)-tetraphenylphosphonium bromide, respectively, with potassium hexabromoplatinate (mole ratio 2: 1). After recrystallization from dimethyl sulfoxide, complexes I, II, and III transform into [Bu₄N]⁺[PtBr₅(DMSO)]⁻ (IV), [Ph₄P]⁺[PtBr₅(DMSO)]⁻ (V), and [Ph₃(n-Am)P]⁺[PtBr₅(DMSO)]⁻ (VI). According to the X-ray diffraction data, the cations of complexes IV–VI have a slightly distorted tetrahedral structure. The N-C and P-C bond lengths are 1.492(7)–1.533(6) and 1.782(10)–1.805(10) ?, respectively. The platinum atoms in the mononuclear anions are hexacoordinated. The dimethyl sulfoxide ligands are coordinated with the Pt atom through the sulfur atom (Pt-S 2.3280(18)–2.3389(11) ?). The Pt-Br bond lengths are 2.4330(6)–2.4724(6) ?.     

一维链状配位聚合物{[p-FBzlPh3P]+[ZnCl2(NA)]-}n的合成与晶体结构

A metal-organic coordination polymer, {[p-FBzlPh₃P] [ZnCl₂(NA)]}_n(1) (NA=nicotinic acid), has been hydrothermally synthesized and characterized by IR, UV-Vis, TG analysis, elemental analysis, fluorescence analysis and single crystal structure determination. Compound 1 crystallizes in the monoclinic system, space group P2₁/n, a=0.983 6(3) nm, b=2.567 0(7) nm, c=1.133 4(3) nm, β=94.46°, V=2.853 0(14) nm³, Z=4, R₁=0.049 3, wR₂=0.126 5 and S=1.037. The structure of compound 1 features as novel one-dimensional structure, and interestingly, the [p-FBzlPh₃P]⁺ counter-cations alternately reside both sides of the one-dimensional anionic chains of the zigza-chain polymer, and the supermolecule is formed by intermolecular weak hydrogen bond. Compound 1 exhibits strong fluorescence in solid state at room temperature. CCDC: 664276.     

聚合物{[CuII(Hpb) (mal)]H2O}n :单体的量子化学计算和磁性研究

{[Cu^Ⅱ（Hpb）（mal）]H=O}n （Hpb=2-2＇-pyridylbenzimidazole, mal=maleic acid） is a helical chain-like polymer complex. In order to investigate the electronic structure of the complex, the monomer Cu^Ⅱ（Hpb）（mal） was obturated with different functional groups respectively. For these selective segments, the geometry optimizations were conducted by using hybrid DFT （B3LYP）methods to find that the structure obturated with H2O was better consistent with the experiment, and then this model would be used to latter calculations, such as the frontier molecular orbital and the NBO charge population analysis. In addition the magnetic behaviors of this complex were analyzed by experiments and the weak antiferromagnetic couple between copper（Ⅱ） ions was observed. The exchange coupling constant was calculated by DFT based on the spin broken symmetry formalism. The calculated coupling constants were in good agreement with the experimental data.     

Complexation between N-allylmorpholinium derivatives and copper(I) halides. Synthesis and crystal structure of π-complex {[C4H8ONH(C3H5)]+}2[Cu2Cl4]2?

Copper(I) -complex {[C₄H₈ONH(C₃H₅)]⁺}₂[Cu₂Cl₄]^2– (I) was obtained by ac electrochemical synthesis from N-allylmorpholine hydrochloride and copper(II) chloride in ethanol and structurally characterized. In structure I, copper and chlorine atoms form unique noncentrosymmetric Cu₂Cl ₄ ^2– fragments. Both crystallographically independent N-allylmorpholinium cations are involved in the -interaction and are coordinated by the copper atom through the C=C bond of the allyl group. The trigonal pyramidal environment of the Cu(1) atom is composed of three chlorine atoms and the C=C bond, while the Cu(2) atom coordinates two chlorine atoms and the C=C bond forming a planar triangle. The extremely strong N-CCl hydrogen bond (HCl 2.2 ) prevents the Cl(1) atom from acting as a bridge and favors the formation of fragments Cu₂Cl ₄ ^2– .__________Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 4, 2005, pp. 306–310.Original Russian Text Copyright © 2005 by Goreshnik, Davydov, Myskiv.     

Theoretical studies on N-loss predissociation mechanisms of N2O+ (A?2Σ+) in Cs symmetry

The N-loss predissociation mechanisms of the A ²Σ⁺ (2 ² A′) state of N₂O⁺ to the first and second dissociation limits were studied in the C _s symmetry. The potential energy curves (PECs) and minimum energy crossing points (MECPs) for the C _s states of N₂O⁺ were calculated at the CAS levels. On the basis of our CAS calculation results (CASPT2 energetic results and CASSCF spin orbit couplings), we suggest two processes for N-loss predissociation mechanisms of A ²Σ⁺ (2 ² A′) to the first and second limits. The first two steps in the two processes are the same: A ²Σ⁺ passes through the 2 ² A′/1 ⁴ A″ MECP and then reaches the 1 ⁴ A″ (1 ⁴Σ⁻) PEC. The 2 ² A′/1 ⁴ A″ MECP has a bent geometry and is slightly higher in energy than the transition state along the 1 ⁴ A″ PEC. Our mechanisms are different from the previously suggested mechanisms (via 1 ⁴Π).     

A Novel Organic–Inorganic Hybrid Polyoxoniobate Constructed from {[Cu(en)(H2O)][HNb6O19]}5? Polyoxoanions and Methane-like {K4Na}5+ Cations

A novel organic–inorganic hybrid polyoxoniobate K₈Na₂{[Cu(en)(H₂O)]₂ [HNb₆O₁₉]₂}·25H₂O (en = ethylenediamine) 1 has been synthesized by the diffusion method and structurally characterized by elemental analyses, IR, UV-Vis spectra, thermogravimetric (TG) analysis and single crystal X-ray diffraction. The structure analysis indicates that 1 consists of two {[Cu(en)(H₂O)][HNb₆O₁₉]}⁵⁻ polyoxoanions linked each other by two methane-like {K₄Na}⁵⁺ cationic clusters. Surface photovoltage spectroscopy (SPS) and electric field induced surface photovoltage spectroscopy (EFISPS) measurements indicate that 1 is the n-type conduction characteristic. In situ UV and CV studies indicate that 1 can stably exist in the larger pH ranges in aqueous solution.     

Crystal structure of [MnII (1,10-C12H8N2)3]2+[(B9C2H11)CoIII(B8C2H10)CoIII(B9C2H11)]2?·CH3CN

A novel compound, [MnPhen₃][(B₉C₂H₁₁)Co(B₈C₂H₁₀)Co(B₉C₂H₁₁)]· CH₃CN (Phen = 1,10-phenantroline), comprising a Co(III) dicobaltacarborane cluster anion has been prepared and characterized by single crystal X-ray diffraction. Crystal data are the following: C₄₄H₅₉B₂₆N₇Co₂Mn, M = 1139.84, triclinic, space group , unit cell parameters: a = 13.2465(11) Å, b = 14.521(2) Å, c = 15.2536(15) Å; α = 77.027(9)°, β = 88.500(8)°, γ = 77.274(9)°; V = 2788.5(5) ų, Z = 2, d _calc = 1.358 g/cm³, T = 295 K, F(000) = 1162, μ = 0.853 mm⁻¹. The structure was solved by the direct and Fourier methods and refined anisotropically (isotropically for hydrogen atoms) using the full-matrix technique to final factors R ₁ = 0.0374, wR ₂ = 0.0915 for 7397 I _hkl ≥2σ_I of 9779 I _hkl measured (diffractometer Enraf-Nonius CAD-4, λMoK _α , graphite monochromator, θ/2θ-scanning). The structure is formed from [MnPhen₃]²⁺ cations, [(B₉C₂H₁₁)×Co(B₈C₂H₁₀)Co(B₉C₂H₁₁)]₂₋ anions, and acetonitrile molecules CH₃CN. Central Mn atom in the cation has a distorted octahedral coordination environment formed by six nitrogen atoms of three bi-dentate Phen ligands, average Mn-N bond length being 2.263(2) Å. The anion has a chain-like structure built from three icosahedra sharing common vertices occupied by the cobalt atoms. The central icosahedron including ten light atoms (8B, 2C) provides two vertices for the cobalt atoms shared with the other icosahedra having 11 light atoms (9B, 2C). The arrangement of-C₂-groups in the anion corresponds to a quasi-gauche-configuration of asymmetric sandwich complexes of both cobalt atoms. Original Russian Text Copyright ? 2005 by T. M. Polyanskaya, V. V. Volkov, and M. K. Drozdova __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 46, No. 4, pp.730–740, July–August, 2005.     

Regioselectivity of the addition of ?CCl3 and ?But radicals to (η2-C70)[Os(CO)(PPh3)2(CNBut)]n (n = 1, 2): an ESR study

The addition of ^•CCl₃ and ^•Bu^t radicals to (η²-C₇₀)Os(CO)(PPh₃)₂(CNBu^t) (1) and (η²-C₇₀)[Os(CO)(PPh₃)₂(CNBu^t)]₂ (3) was studied by ESR spectroscopy. The metal fragment in complex 1 does not influence the regioselectivity of the addition of the radicals to it. The stability of the spin adducts formed upon addition of free radicals to complexes 1 and 3 is mainly governed by delocalization of the unpaired electron over three hexagonal rings.     

有机金属衍生物α，β-［(RSn)3GeW9O37］7-的合成与性质研究

本文报道了α，β-M₄H₃［(RSn)₃GeW₉O₃₇］·nH₂O(M=Bu₄N⁺, Me₄N⁺; R=Bu, Ph)杂多配合物的合成、表征及催化性能研究、元素分析、红外光谱和紫外光谱、¹H、¹¹⁹Sn和¹⁸³W核磁共振谱、激光飞行时间(TOF)质谱和极谱数据表明，这些新化合物为三取代的Keggin结构，三个(RSn)³⁺属不同的M₃O₁₃单元并且彼此共角相连，标题杂多化合物主要以单体形式存在且对烯烃环氧化反应具有催化活性。     

The QCT calculation of the rate constants for the N(4S)+O2(X3Σ g ? ) →NO(X2Π)+O(3P) reaction

A quasi-classical trajectory (QCT) calculation with the fourth-order explicit symplectic algorithm for the N(⁴S) + O₂(X³Σ_g⁻) → NO(X²Π) + O(³P) reaction has been performed by employing the ground and first-excited potential energy surfaces (PESs). Since the translational temperature considered is up to 5000 K, the larger relative translational energy and the higher vibrational and rotational level of O₂ molecule have been taken into account. The affect of the relative translational energy, the vibrational and rotational level of O₂ molecule in the reaction cross-sections of the ground and first-excited PESs has been discussed in a extensive range. And we exhibit the dependence of microscopic rate constants on the vibrational and rotational level of O₂ molecule at T = 4000 K. The thermal rate constants at the translational temperature betweem 300 and 5000 K have been evaluated and the corresponding Arrhenius curve has been fitted for reaction (1). It is found by comparison that the thermal rate constants determined in this work have a better agreement with the experimental data and provide a more valid theoretical reference.     

多羟基甾醇25(R)-异螺甾环-5-烯-2β,3α,19-三醇的合成

以薯蓣皂素为原料, 经过磺酰酯化、N-溴代丁二酰亚胺(NBS)氧化加成、Pb(OAc)₄远程氧化关环、消去反应、间氯过氧苯甲酸(mCPBA)氧化、高氯酸开环及锌粉还原7步反应, 合成多羟基甾体25(R)-异螺甾环-5-烯-2β,3α,19-三醇. 并用IR, ¹H NMR, ¹³C NMR, MS及元素分析对各中间体及目标化合物进行了表征.     

Mixed-Valence 24-Vanadophosphate Decorated with Six RuII(dmso)3 Groups: [{RuII3(dmso)9PVV11VIVRuIIIO37(OH)3}2]8?

The mixed-valence 24-vanadophosphate (1) has been synthesized and characterized in the solid state by IR, magnetism, EPR, XPS, and elemental analysis. Single-crystal X-ray analysis was carried out on (Na-1), which crystallizes in the triclinic system, space group , with a = 17.168(3) ?, b = 18.1971(14) ?, c = 20.1422(13) ?, α = 114.753(3)°, β = 99.390(4)°, γ = 95.124(4)°, and Z = 2. Polyanion 1 has an unusual, open structure composed of 2 Ru^IIIO₆ octahedra, 2 V^IVO₆ octahedra, 14 V^VO₅ square-pyramids, 8 V^VO₄ tetrahedra, and 2 PO₄ tetrahedra which are all directly linked via edges and corners. The outer surface of 1 is decorated with six Ru^II(dmso)₃ groups. XPS studies on Na-1 confirm the presence of 2 Ru^III and 6 Ru^II as well as 22 V^V and 2 V^IV centers. Magnetic susceptibility data on Na-1 show that the V^IV–Ru^III pairs are coupled antiferromagnetically, with J ₁ = −13 K and J ₂ ∼ −3 K. We did not detect any peak in our EPR measurements on Na-1, thus supporting the conclusion that Na-1 is diamagnetic in its ground state. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. In Memoriam Prof. F. A. Cotton     

A novel 2D organic-inorganic hybrid 3d–4f polyoxometalate built by [Gd(α-PW11O39)2]11? units and [Cu(Dap)2]2+ bridges

A novel 2D organic-inorganic hybrid 3d–4f polyoxometalate [Cu(Dap)₂(H₂O)][Cu(Dap)₂]_4.5[Gd(α-PW₁₁O₃₉)₂] · 5H₂O (I) (Dap = 1,2-diaminopropane) built by [Gd(α-PW₁₁O₃₉)₂]¹¹⁻ units and [Cu(Dap)₂]²⁺ bridges has been synthesized hydrothermally by the reaction of GdCl₃, CuCl₂ · 2H₂O, Na₉[A-α-PW₉O₃₄] · 7H₂O, and Dap and characterized by elemental analysis, IR spectrum, UV spectrum, powder X-ray diffraction, and single-crystal X-ray diffraction. Single-crystal structural analysis shows that I displays an interesting 2D 3d–4f heterometallic sheet architecture with a 5-connected topology constructed from 1: 2-type [Gd(α-PW₁₁O₃₉)₂]¹¹⁻ subunits and [Cu(Dap)₂]²⁺ bridges. To the best of our knowledge, I represents a rare organic-inorganic hybrid 2D 3d–4f heterometallic monovacant Keggin phosphotungstate.     

离子化合物{[2-(3′-pyridyl)benzimidazoleH2]2+·[SbCl4]-·Cl-}4的水热合成、晶体结构及抑菌活性

A new ionic compound {[2-(3′-pyridyl)benzimidazoleH₂]²⁺·[SbCl₄]^-·Cl^-}₄ was synthesized by the hydrothermal reaction of o-diaminobenzene, nicotinic acid with SbCl₃ in 1∶1 HCl solution. The structure was characterized by chemical analysis, elemental analysis and IR patterns. The single crystal structure was determined by X-ray single crystal diffraction. It crystallizes in monoclinic system, space group P2₁/n with a=2.107 9(4) nm, b=1.482 0(3) nm, c=2.113 4(4) nm, β=93.44(3)°, Z=4, V=6.590(2) nm³, D_c=2.001 g·cm^-3, μ=2.480 mm^-1, F(000)=3840, R₁=0.0468, wR₂=0.1163. The single crystal structure indicates that the four chlorines coordinated to the antimony atom forms a distorted triangle bipyramid configuration together with the lone electron pair on the Sb atom. The [SbCl₄]^- to 2-(3′-pyridyl)benzimidazole cation and Cl^- by weak interaction forms the ionic crystal. It has been proved that the title compound has antibacterial activity. CCDC: 283824.     

Synthesis and crystal structure of π-complex of copper(I) with 1-allylbenzimidazolium cation [C7H5N2H(C3H5)]+ [Cu3Cl4]?

Single crystals of [C₇H₅N₂H(C₃H₅)]⁺[Cu₃Cl₄]^– were obtained for the first time by ac electrochemical synthesis from 1-allylbenzimidazolium and copper(II) chlorides in ethanol and structurally characterized. The unit cell parameters are a=8.6755(9) , b=8.846(1) , c=10.4540(7) , =85.36(1)°, =70.529(7)°, =83.29(1)° , V=750.5(3) ³, space group P , R(F)=0.0551. In the -complex, the copper and chlorine atoms form complicated infinite chains along the x axis. The 1-allylbenzimidazolium cation functions as an original bridge: it is coordinated by the Cu atom of one cuprous-chloride chain through the C=C bond of the allyl group and forms a N-HCl hydrogen bond with another inorganic chain through the N atom of the imidazole ring. The trigonal pyramidal environment of the Cu(1) atom includes three Cl atoms and the C=C bond; the environments of the Cu(2), Cu(3), and Cu(3a) are composed only of chlorine atoms. The positions of the Cu(2) and Cu(3a) atoms are partially disordered, which is manifested by the high thermal parameters for the Cu(2) atom and by the splitting of another copper atom into two equally occupied positions Cu(3) and Cu(3a).Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 3, 2005, pp. 199–203.Original Russian Text Copyright © 2005 by Goreshnik, Schollmeyer, Myskiv.This revised version was published online in April 2005 with a corrected cover date.This revised version was published online in April 2005 with a corrected cover date.     

氰根桥联FeⅢ-CuⅡ一维配合物{[Fe(1-CH3im)(CN)4(μ-CN)Cu(cyclam)]·H2O}n的合成、结构及磁性研究

基于构筑单元K₂[Fe(1-CH₃im)(CN)₅] 和[Cu(cyclam)] (ClO₄)₂, 合成了一个氰根桥联Fe^Ⅲ-Cu^Ⅱ中性一维化合物{[Fe(1-CH₃im)(CN)₄(μ-CN)Cu(cyclam)] ·H₂O}_n(1-CH₃im=1-甲基咪唑;cyclam=1, 4, 8, 11-四氮杂环十四烷) (1), 并通过X-射线单晶分析表征其结构 特征。结果表明:化合物(1)是由氰根桥联的杂金属组成的聚合物, 其结构属于三斜晶系, P1空间群, a=0.832 56(17) nm, b= 0.899 38(18) nm, c=0.998 3(2) nm, α=111.94(3)°, β=95.06(3)°, γ=116.90(3)°, V=0.587 7(2) nm³, Z=1, D_c=1.554 g·cm^-3, μ=1.558 mm^-1, F(000)=286, R₁=0.051 9, wR₂=0.135 3。磁性研究表明:配合物1中Cu^Ⅱ和低自旋的Fe^Ⅲ离子之间存在弱的铁磁耦合作用。     

氰根桥联FeⅢ-CuⅡ一维配合物{[Fe(1-CH3im)(CN)4(μ-CN)Cu(cyclam)]·H2O}n的合成、结构及磁性研究

基于构筑单元K2[Fe(1-CH3im)(CN)5]和[Cu(cyclam)](ClO4)2,合成了一个氰根桥联FeⅢ-CuⅡ中性一维化合物{[Fe(1-CH3im)(CN)4(μ-CN)Cu(cyclam)]·H2O}n(1-CH3im=1-甲基咪唑;cyclam=1,4,8,11-四氮杂环十四烷)(1),并通过X-射线单晶分析表征其结构特征。结果表明:化合物(1)是由氰根桥联的杂金属组成的聚合物,其结构属于三斜晶系,P1空间群,a=0.832 56(17)nm,b=0.899 38(18)nm,c=0.998 3(2)nm,α=111.94(3)°,β=95.06(3)°,γ=116.90(3)°,V=0.587 7(2)nm3,Z=1,Dc=1.554 g·cm-3,μ=1.558 mm-1,F(000)=286,R1=0.051 9,wR2=0.135 3。磁性研究表明:配合物1中CuⅡ和低自旋的FeⅢ离子之间存在弱的铁磁耦合作用。     

Density functional study of magnetic exchange of dinuclear manganese complexes with the heteropolymolyanion: [MnII2(X n +Mo9O33)2]2( n ?10)? (X = PV, AsV, SeVI)

The magnetic exchange interactions between the dimanganese(II)-substituted complexes and the heteropolymolyanion, [Mn^II ₂(X ⁿ⁺Mo₉O₃₃)₂]^2(n−10)− (X = P^V(I), As^V(II) and Se^VI(III)), are investigated by using density functional theory combined with broken-symmetry approach (DFT-BS) method. The calculated magnetic exchange coupling constant (J) of complex II is in reasonable agreement with the responding experimental value and the negative J values indicate that antiferromagnetic exchange interactions exist in these complexes. Furthermore, the influence of the central heteroatom on the exchange coupling within the dimanganese core unit is studied from standpoints of geometry, spin density and frontier orbitals. It demonstrates that the change of the heteroatom X via P^V-As^V-Se^VI elongates the distances of Mn₁...Mn₂ and shortens the distances of O_b...O_b, and reduces the effectiveness of the superexchange pathways, consequently, decreasing the magnitude of the antiferromagnetic coupling constant, J, of these species. Supported by the National Natural Science Foundation of China (Grant No. 20703008) and Program for Changjiang Scholars and Innovative Research Team in University (Grant No. IRT0714)     

吡啶配位的夹心型杂多阴离子{[Na(H2O)2]3[Ni(C5H5N)]3(AsW9O33)2}9-的结构及磁学性质

The pyridine coordinated sandwich-type heteropolytungstate Na7[Ni（H2O）6] { [Na（H2O）2]3[Ni（C5H5N）]3（AsW9O33）2}·28H2O was obtained by the reaction of Na2WO4·2H2O, NaAsO2 and pyridine with NiCl2·6H2O at pH =7.0 and characterized by elemental analysis, IR, UV-Vis,^1H NMR spectra and magnetic measurement. The structure of this heteropolytungstate was determined by X-ray diffraction analysis, which crystallized in triclinic system, space group P1 with a= 1.3153（9） nm, b= 1.7228（12） nm, c=2.6866（19） nm, a=74.130（11）°,β=78.032（12）°, γ = 73.179（12）° and Z= 2, R1 = 0.0604, wR2 = 0.0915 [I〉 2σ（I）]. Polyanion {[Na（H2O）2]3[Ni（C5H5N）]3（AsW9O33）2}^9- has approximately C3 symmetry, and three pyridine coordinated Ni（C5H5N）^2＋ and three Na（H2O）2^＋ are encapsulated between two AsW9O33^9- . Magnetic measurements show that central Ni3 unit in the polyanion exhibits ferromagnetic Ni-Ni exchange interactions （J=6.17 cm^-1）.     

Low-temperature X-ray diffraction study of [CuII(1,10-C12H8N2)3]2+{CoIII[η5-(3)-1,2-C2B9H11]2} 2? ·CH3CN

Single crystal XRD is used to study the crystal structure of a new compound containing the dicarbollyl cluster anion Co(III) with the composition [CuPhen₃][Co(C₂B₉H₁₁)₂]₂·CH₃CN, where Phen is 1,10-phenanthroline. The crystallographic data: C₄₆H₇₁B₃₆N₇Co₂Cu, M = 1292.66, monoclinic system, P2₁/c space group, unit cell parameters a = 14.7178(2) ?, b = 19.5640(4) ?, c = 22.8663(5) ?, β = 106.6601(7)°, V = 6307.75(33) ?³, Z = 4, d _x = 1.361 g/cm³, T = 100 K, μ = 0.90 mm⁻¹. The structure is solved by the direct method and refined by the full-matrix LSM in an anisotropic-isotropic (for H atoms) approximation up to the final agreement factors R ₁ = 0.0370, wR ₂ = 0.0869 for 13,807 I _hkl ≥ 2 σ _I out of 18,295 measured I _hkl . The structure consists of [CuPhen₃] cations, Co(C₂B₉H₁₁)₂ anions, and acetonitrile molecules MeCN. The central Cu atom in the cation in the general position, and its coordination geometry is a distorted extended octahedron formed by six nitrogen atoms of the three bidentate Phen ligands. The coordination of Cu(II) in the cation is (2+2+2) with two long axial and four shorter equatorial Cu-N bonds, whose average lengths are 2.239(2) ? and 2.077(1) ? respectively. Each anion has its own position of the -C₂-groups; for Co(1), it is a quasi-gauche-configuration; for Co(2), a quasi-trans-configuration.