V16Sb4O42(H2O){VO(C6H14N2)2}4]: a terminal expansion to a polyoxovanadate archetype

The charge-neutral antimonatopolyoxovanadium(IV) cluster [V(IV)16Sb(III)4O42(H2O){V(IV)O(C6H14N2)2}4].10H2O.C6H14N2 was obtained under solvothermal conditions. The central cluster fragment, [V(IV) 16Sb(III)4O42], is a derivative of the [V18O42] archetype and is formed by replacing two VO5 polyhedra by two Sb2O5 units. The {V20Sb4} structure expands the {V16Sb4} motif by the addition of four square-pyramidal, terminal VO(1,2-diaminocyclohexane)2 groups. At low temperatures, the magnetic ground state is characterized by four independent S = 1/2 sites.     

Sulfosalts with alkaline earth metals. Centrosymmetric vs acentric interplay in Ba3Sb4.66S10 and Ba2.62Pb1.38Sb4S10 based on the Ba/Pb/Sb ratio. Phases related to arsenosulfide minerals of the rathite group and the novel polysulfide Sr6Sb6S17

The new compounds, Sr6Sb6S17, Ba2.62Pb1.38Sb4S10, and Ba3Sb4.66S10 were prepared by the molten polychalcogenide salt method. Sr6Sb6S17 crystallizes in the orthorhombic space group P2(1)2(1)2(1) with a = 8.2871(9) A, b = 15.352(2) A, c = 22.873(3) A, and Z = 4. This compound presents a new structure type composed of [Sb3S7]5- units and trisulfide groups, (S3)2-, held together by Sr2+ ions. The [Sb3S7]5- fragment is formed from three corner-sharing SbS3 trigonal pyramids. The trisulfide groups are separated from the [Sb3S7]5- unit and embedded between the Sr2+ ions. Ba3Sb4.66S10 and Ba2.62Pb1.38Sb4S10 are not isostructural but are closely related to the known mineral sulfosalts of the rathite group. Ba3Sb4.67S10 is monoclinic P2(1)/c with a = 8.955(2) A, b = 8.225(2) A, c = 26.756(5) A, beta = 100.29(3) degrees, and Z = 4. Ba2.62Pb1.38Sb4S10 is monoclinic P2(1) with a = 8.8402(2) A, b = 8.2038(2) A, c = 26.7623(6) A, beta = 99.488(1) degrees, and Z = 4. The Sb atoms are stabilized in SbS3 trigonal pyramids that share corners to build ribbonlike slabs, which are stitched by Ba/Pb atoms to form layers perpendicular to the c-axis. These materials are semiconductors and show optical band gaps of 2.10, 2.14, and 1.64 eV for Sr6Sb6S17, Ba3Sb4.66S10, and Ba2.62Pb1.38Sb4S10, respectively. Raman spectroscopic characterization is reported. Sr6Sb6S17, Ba3Sb4.66S10, and Ba2.62Pb1.38Sb4S10 melt congruently at 729, 770, and 749 degrees C, respectively.     

阴极铜化学标准样品的研制

经成分设计、原料选取、熔铸加工、均匀性检验等研制了阴极铜化学标准样品。以高纯铜为主原料,加入Si,Zn,S,Se等18种杂质元素制备而成,各定值元素含量呈梯度上升分布。经检验该标准样品成分均匀,稳定性好,18种杂质元素的定值结果分别为Se 0.000 02%~0.000 87%,Te 0.000 03%~0.001 1%,Bi 0.000 02%~0.001 2%,Cr 0.000 02%~0.003 2%,Mn 0.000 03%~0.002 7%,Sb 0.000 02%~0.003 1%,Cd 0.000 01%~0.003 0%,As0.000 01%~0.003 8%,P 0.000 05%~0.005 6%,Pb 0.000 03%~0.004 4%,S 0.000 15%~0.008 2%,Sn 0.000 01%~0.002 6%,Ni0.000 09%~0.006 0%,Fe 0.000 16%~0.005 4%,Si 0.000 15%~0.003 4%,Zn 0.000 04%~0.005 2%,Co 0.000 01%~0.003 5%,Ag 0.000 07%~0.007 2之间。定值结果的扩展不确定度为0.000 01%~0.000 3%(k=2)。研制的阴极铜化学标准样品已被批准为国家级标准样品,标准编号为GSB 04–2554–2010。该标准样品成分设计合理、涵盖范围广,可用于阴极铜及部分铜合金的分析检测。     

Solvothermal Synthesis and Crystal Structure of a Layered Thioantimonate(Ⅲ) [C4H9NH3]2Sb4S7

An inorganic-organic hybrid thioantimonate(Ⅲ) [CH3(CH2)3NH3]2Sb4S7 1 with layered structure was synthesized by solvothermal method.1 crystallizes in the triclinic system, space group P with a = 7.0124(11), b = 11.919(2), c = 14.879(3) (A), α = 108.791(3), β = 102.441(3), γ = 92.846(2)o, V = 1140.1(3) (A)3, Mr = 859.71, Z = 2, Dc = 2.504 g/cm3, μ= 5.324 mm-1, F(000) = 804, S = 1.013, the final R = 0.0297 and wR = 0.0618 for 3534 observed reflections with I＞2σ(I). 1 consists of [C4H9NH3] cations and two-dimensional [Sb4S7]n2n-anion which is composed of three SbS3 trigonal pyramids and one SbS4 unit joined by sharing common corners. The anionic layers are stacked perpendicularly to the c axis of the unit cell forming two-dimensional channels between the layers. The [C4H9NH3] cations interdigitate in a bilayer and reside in the 2D channels leading to a sandwich-like arrangement of the anion and cations.     

Solvothermal Synthesis and Crystal Structure of a Layered Thioantimonate(Ⅲ) [C_4H_9NH_3]_2Sb_4S_7

An inorganic-organic hybrid thioantimonate(Ⅲ) [CH3(CH2)3NH3]2Sb4S7 1 with layered structure was synthesized by solvothermal method. 1 crystallizes in the triclinic system,space group P1 with a=7.0124(11),b=11.919(2),c=14.879(3),α=108.791(3),β=102.441(3),γ=92.846(2)o,V=1140.1(3)3,Mr=859.71,Z=2,Dc=2.504 g/cm3,μ =5.324 mm-1,F(000)=804,S=1.013,the final R=0.0297 and wR=0.0618 for 3534 observed reflections with I > 2σ(I). 1 consists of [C4H9NH3]+ cations and two-dimensional [Sb4S7]n2n- anion which is composed of three SbS3 trigonal pyramids and one SbS4 unit joined by sharing common corners. The anionic layers are stacked perpendicularly to the c axis of the unit cell forming two-dimensional channels between the layers. The [C4H9NH3]+ cations interdigitate in a bilayer and reside in the 2D channels leading to a sandwich-like arrangement of the anion and cations.     

Macrocyclic amines as structure-directing agents for the synthesis of three-dimensional antimony-sulfide frameworks

A new family of antimony sulfides, incorporating the macrocyclic tetramine 1,4,8,11-tetraazacyclotetradecane (cyclam), has been prepared by a hydrothermal method. [C10N4H26][Sb4S7] (1), [Ni(C10N4H24)][Sb4S7] (2), and [Co(C10N4H24)]x[C10N4H26](1-x)[Sb4S7] (0.08 < or = x < or = 0.74) (3) have been characterized by single-crystal X-ray diffraction, elemental analysis, thermogravimetry, and analytical electron microscopy. All three materials possess the same novel three-dimensional Sb4S7(2-) framework, constructed from layers of parallel arrays of Sb4S8(4-) chains stacked at 90 degrees to one another. In 1, doubly protonated macrocyclic cations reside in the channel structure of the antimony-sulfide framework. In 2 and 3, the cyclam acts as a ligand, chelating the divalent transition-metal cation. Analytical and X-ray diffraction data indicate that the level of metal incorporation in 2 is effectively complete, whereas in 3, both metalated and nonmetalated forms of the macrocycle coexist within the structure.     

配合物[Sb(mpo)2Cl]的合成及晶体结构(Hmpo = 2-巯基氧化吡啶)

标题化合物 C10H8ClN2O2S2Sb 由[C5H5NH][SbCl4]与 2-巯基氧化吡啶钠盐(Nampo)反应制得。其结构通过元素分析、IR 进行了表征,用 X-射线衍射法测定了该化合物的晶体结构。结果表明,晶体属于三斜晶系, 空间群为 P1, Mr = 409.50, 晶体参数:a = 9.4022(6), b =10.2910(7), c = 14.4631(9) ?, α= 104.321(1), β = 96.978(1), γ = 90.179(1)?, V = 1345.09(15)?3, Z = 4, Dc = 2.022 g/cm3, μ = 2.553 mm–1, F(000) = 792。晶体结构用直接法解出, 经全矩阵最小二乘法修正,最终结构偏离因子 R = 0.0368, wR = 0.0854。化合物分子中, 锑与一个氯原子和两个配体 mpo 配位,形成五配位变形的四角锥构型配合物。在晶胞堆积图中,锑原子又与另一分子中的氯原子以次级键形式作用,形成缺位配位多面体构型。     

Solvothermal syntheses, crystal structures, and thermal properties of new manganese thioantimonates(III): The first example of the thermal transformation of an amine-rich thioantimonate into an amine-poorer thioantimonate

Two new neutral thioantimonates(III) were first prepared by the reaction of elemental manganese, antimony, and sulfur in tren (tren = tris(2-aminoethyl)amine, C6H18N4) at 140 degrees C. In the amine-rich compound [Mn(tren)]2Sb2S5 (1) the trigonal SbS3 pyramids are connected via common corners (S(3)) into the tetradentate [Sb2S4]4- anion. Four S atoms have bonds to the manganese atoms of the [Mn(tren)2+] cations. A special structural feature is the large Sb-S(3)-Sb(a) angle of 134 degrees. Density functional calculations clearly demonstrate that this large angle results from the steric interactions between the two Mn(tren) subunits. In the crystal structure of the amine-poorer compound [Mn(tren)]2Mn2Sb4S10 (2), MnS4 tetrahedra and SbS3 pyramids are linked via common corners and edges to form a new heterometallic [Mn2Sb4S10] core. The [Mn(C6H18N4)2+] cations are located at the periphery of the core and are bound to the [Mn2Sb4S10] unit via two S atoms. The thermal behavior of both compounds was investigated using simultaneous thermogravimetry (TG), differential thermoanalysis, and mass spectroscopy. The amine-richer compound 1 decomposes in three steps upon heating. After the first TG step an intermediate phase is formed, which was identified as the amine-poorer compound 2 by X-ray diffraction. Reaction of compound 2 at 140 degrees C with an excess of tren forms the amine-rich compound 1.     

Structures of Sb(OC(6)H(3)Me(2)-2,6)(3) and Sb(OEt)(5) x NH(3): the first authenticated monomeric Sb(OR)(n) (n = 3, 5)

The first monomeric antimony alkoxides, Sb(OC(6)H(3)Me(2))(3) (1) and Sb(OEt)(5) x NH(3) (2), have been crystallographically characterized. The former adopts a trigonal pyramidal geometry, while the latter is octahedral about antimony; hydrogen bonding between NH(3) and SbOEt groups in Sb(OEt)(5) small middle dotNH(3) creates a one-dimensional lattice arrangement. Reaction of pyridine with SbCl(5) in EtOH/hexane yields the salt [Hpy(+)](9)[Sb(2)Cl(11)(5)(-)][Cl(-)](4) (3), which has also been crystallographically characterized. Crystallographic data: 1, C(24)H(27)O(3)Sb, a = 10.9080(2), b = 11.9660(2), c = 17.7260(4) A, alpha = 109.740(1) degrees, monoclinic P2(1)/c (unique axis a), Z = 4; 2, C(10)H(28)NO(5)Sb, a = 7.7220(1), b = 19.0700(2), c = 21.6800(3) A, beta = 93.4960(7) degrees, monoclinic P2(1)/c, Z = 8; 3, C(45)H(54)Cl(15)N(9)Sb(2), a = 13.4300(2), b = 14.4180(2), c = 17.4180(3) A, alpha = 82.7650(7), beta = 77.5570(7), gamma = 70.7670(7) degrees, triclinic P1, Z = 2.     

超高效液相色谱-串联质谱法测定动物源性食品中10种水杨酰胺类化合物

建立了动物源性食品中10种水杨酰胺类化合物(5-氯水杨酰苯胺、4'-溴水杨酰苯胺、3',4'-二氯水杨酰苯胺、4',5-二氯水杨酰苯胺、3',4',5-三氯水杨酰苯胺、5-溴-4'-氯水杨酰苯胺、3,5-二溴水杨酰苯胺、4',5-二溴水杨酰苯胺、3,4',5-三溴水杨酰苯胺、3,3',4',5-四氯水杨酰苯胺)的超高效液相色谱-串联质谱(UPLC-MS/MS)检测方法。样品经乙腈萃取,氨基固相萃取小柱(SPE)净化,T3色谱柱分离后,以甲醇-0.1%甲酸溶液梯度洗脱,串联质谱电喷雾负模式扫描,多反应监测模式检测,外标法定量。结果表明,10种目标物在一定范围内线性关系良好,相关系数(r~2)不小于0.995 7,检出限为0.5~1.0μg/kg,定量下限为1.5~3.0μg/kg;加标水平为1.5~30.0μg/kg时,回收率为81.0%~106%,相对标准偏差(RSD,n=6)不大于7.5%。该方法净化效果好、定量准确、灵敏快速,适用于动物源性食品中10种水杨酰胺类化合物的检测与确证。     

链状钼硫, 钨硫原子簇合物的合成和成簇规律的研究

本文报道了不同酸性条件下合成的一系列链状钼硫、钨硫簇化合物, 发现硫代钼(钨)酸铵的成簇与酸的强度、浓度、H^+/M(M=Mo、W)比、溶剂、反应气氛密切相关。测定了四个新簇合物的晶体结构, 其中[MoW2S10]^2^-晶体是第一次报道的Mo-W-S混合簇化合物。     

Solvent Dependence of the Hydrolysis Products of Mn2Sb4(OEt)16

The hydrolysis-condensation pathways of Mn2Sb4(OEt)16 in various ethanol-toluene solvents have been studied for h < 1.5 (h = H2O/Mn2Sb4(OEt)16). The hydrolysis was performed by slow addition of H2O diluted with the ethanol-toluene solvent. Mn2Sb4(OEt)16 and its hydrolysis products were studied by FT-IR spectroscopy, SEM-EDS and single-crystal X-ray diffraction. The hydrolysis pathway for a given h-value was found to depend on the solvent composition. In ethanol-rich solvent mixtures, Mn7Sb4O4(OEt)18(HOEt)2 was obtained in maximum yield at h = 1.14, and in toluene-rich solvents, Mn8Sb4O4(OEt)20 was obtained in maximum yield at h = 1.0. In both cases, the remaining Sb was found as nonhydrolyzed Sb(OEt)3. The structures of the heterometallic ethoxides Mn2Sb4(OEt)16, Mn7Sb4O4(OEt)18(HOEt)2 and Mn8Sb4O4(OEt)20 have been determined earlier by single-crystal X-ray diffraction. According to FT-IR evidence the molecular structures of the latter two are retained almost intact in solution, whereas the first one changes appreciably. The hydrolysis products of Mn2Sb4(OEt)16 are compared with those of Ni2Sb4(OEt)16, and the structural and compositional changes in different solvents and at different h-values are discussed.     

Preparation and Optical Properties of Sb2S3 Microcrystallite Doped Silica Glasses by the Sol-Gel Process

The sol-gel process has been applied to the preparation of nano-size Sb2S3 crystallite doped silica glasses and thin films. Silica glasses containing 1–1.5 wt% Sb2S3 are prepared by hydrolysis of complex solution of Si(OC2H5)4, SbCl3 and SC(NH2)2, and subsequent heat treatment. The nano-size crystallite in the matrix is observed by means of TEM. The transmission spectra of the films show that the transmission valley shifts toward longer wavelengths with increasing heat treatment time and temperature. Second harmonic generation (SHG) has been observed in the glasses illuminated with intense 1.06 m and frequency-doubled laser beams from mode-locked Nd:YAG laser.     

Ruthenium(II) ammine and hydrazine complexes with [N(Ph2PQ)2]- (Q = S, Se) ligands

Reactions of coordinatively unsaturated Ru[N(Ph2PQ)2]2(PPh3) (Q = S (1), Se (2)) with pyridine (py), SO2, and NH3 afford the corresponding 18e adducts Ru[N(Ph2PQ)2]2(PPh3)(L) (Q = S, L = NH3 (5); Q = Se, L = py (3), SO2 (4), NH3 (6)). The molecular structures of complexes 2 and 6 are determined. The geometry around Ru in 2 is pseudo square pyramidal with PPh3 occupying the apical position, while that in 6 is pseudooctahedral with PPh3 and NH3 mutually cis. The Ru-P distances in 2 and 6 are 2.2025(11) and 2.2778(11) A, respectively. The Ru-N bond length in 6 is 2.185(3) A. Treatment of 1 or 2 with substituted hydrazines L or NH2OH yields the respective adducts Ru[N(Ph2PQ)2]2(PPh3)(L) (Q = S, L = NH2NH2 (12), t-BuNHNH2 (14), l-aminopiperidine (C5H10NNH2) (15); Q = Se, L = PhCONHNH2 (7), PhNHNH2 (8), NH2OH (9), t-BuNHNH2 (10), C5H10NNH2 (11), NH2NH2 (13)), which are isolated as mixtures of their trans and cis isomers. The structures of cis-14 and cis-15 are characterized by X-ray crystallography. In both molecular structures, the ruthenium adopts a pseudooctahedral arrangement with PPh3 and hydrazine mutually cis. The Ru-N bond lengths in cis-14.CH2Cl2 and cis-15 are 2.152(3) and 2.101(3) A, respectively. The Ru-N-N bond angles in cis-14.CH2Cl2 and cis-15 are 120.5(4) and 129.0(2) degrees, respectively. Treatment of 1 with hydrazine monohydrate leads to the isolation of yellow 5 and red trans-Ru[N(Ph2PS)2]2(NH3)(H2O) (16), which are characterized by mass spectrometry, 1H NMR spectroscopy, and elemental analyses. The geometry around ruthenium in 16 is pseudooctahedral with the NH3 and H2O ligands mutually trans. The Ru-O and Ru-N bond distances are 2.118(4) and 2.142(6) A, respectively. Oxidation reactions of the above ruthenium hydrazine complexes are also studied.     

Extending the time: solvothermal syntheses, crystal structures, and properties of two non-isostructural thioantimonates with the composition [Mn(tren)]Sb2S4

The two novel compounds, [Mn(tren)]Sb2S4 (1 and 2), were obtained by the reaction of elemental Mn, Sb, and S in aqueous solutions of tren (tren = tris(2-aminoethyl)amine, C6H18N4) after different reaction times. Compound 1 is formed up to a reaction time of 13 d, and an extension of the reaction time leads to the formation of 2. Both compounds crystallize in monoclinic space groups (1, P2(1)/c; 2, C2/c). In 1, the two unique SbS3 trigonal pyramids share a common S atom to form a Sb2S5 unit. Two S atoms of this group have a bond to Mn2+ yielding a MnSb2S3 heteroring in the boat conformation. The Sb2S5 moieties are joined via common corners into the final undulated [Sb2S4]2- anion which is directed along [001]. The structure of 2 contains the [Mn(tren)]2+ ion, one SbS3 pyramid, and a SbS4 unit. Two symmetry-related SbS4 groups share an edge, forming a Sb2S6 group containing a Sb2S2 ring. This group is joined via corners to two SbS3 pyramids on both sides producing a Sb4S4 ring. The Sb2S2 and Sb4S4 rings are condensed into the final [Sb2S4]2- anion which runs along [010]. The [Mn(tren)] groups are bound to the thioantimonate(III) backbone on opposite sides of the Sb4S4 ring, and a small MnSbS2 ring is formed. In both structures, weak S...H bonds are found which may contribute to the stability of the materials. The two compounds decompose in one step upon heating, and only MnS and Sb2S3 could be identified as the crystalline part of the decomposition products. Both compounds can also be prepared under solvothermal conditions using MnSb2S4 as starting material. Compounds 1 and 2 are obtained from this ternary material in a high yield.     

Novel lanthanoid thioantimonates: the first coexistence of different types of thioantimonate anions in the same framework

Two novel lanthanoid thioantimonates [Sm(4)(tepa)(4)(μ-η(2),η(3)-Sb(3)S(7))(2)(μ-Sb(2)S(4))] (1, tepa = tetraethylenepentamine) and [Eu(2)(tepa)(2)(μ-SbS(3))(μ-OH)](2)(SbS(4))(OH)·H(2)O (2) were solvothermally synthesized. Compound 1 represents the only example of different types of [Sb(3)S(7)](5-) and [Sb(2)S(4)](2-) anions coexisting in the same lanthanoid thioantimonate framework, while 2 displays rare mixed-valent Sb(3+)/Sb(5+) character with the Sb(3+) in a noncondensed pyramid [Sb(III)S(3)](3-). The theoretical band structure and luminescence properties have also been investigated.     

Fe_3O_4@ILs-β-CDCP磁固相萃取-电感耦合等离子体发射光谱法同时测定环境水样中铅和锑

本文制备了磁性固相萃取材料Fe_3O_4@ILs-β-CDCP,并对其进行了表征。详细考察了Fe_3O_4@ILs-β-CDCP萃取Pb(Ⅱ)和Sb(Ⅲ)的各种影响因素,如溶液pH值、样品体积、洗脱剂浓度和用量、洗脱剂类型、共存离子影响等。基于此,建立了磁固相萃取-电感耦合等离子体发射光谱法(ICP-OES)同时测定Pb(Ⅱ)和Sb(Ⅲ)的新方法。在优化的条件下,该方法对Pb(Ⅱ)和Sb(Ⅲ)的检出限分别为1.50和0.54ng/mL,相对标准偏差(RSDs)分别为5.9%和2.4%(n=6,c=100.0ng/mL)。将该方法应用于实际水样中Pb(Ⅱ)和Sb(Ⅲ)的测定,其回收率分别为77.8%~106%和82.4%~107%。方法具有检出限低、操作简便等优势。     

Growth of Sb(2)E(3) (E = S, Se) polygonal tubular crystals via a novel solvent-relief-self-seeding process

A novel solvent-relief-self-seeding (SRSS) process was applied to grow bulk polygonal tubular single crystals of Sb(2)E(3) (E = S, Se), using SbCl(3) and chalcogen elements E (E = S, Se) as the raw materials at 180 degrees C for 7 days in ethanol solution. The products were characterized by various techniques, including X-ray powder diffraction (XRD), scanning electronic microscope (SEM), transmission electronic microscope (TEM), electronic diffraction (ED), and X-ray photoelectron spectra (XPS). The calculated electrical resistivities of the tubular single crystals in the range 20-320 K were of the order of 10(5)-10(6) Omega cm for Sb(2)S(3) and 10(3)-10(4) Omega cm for Sb(2)Se(3), respectively. The studies of the optical properties revealed that the materials formed had a band gap of 1.72 eV for Sb(2)S(3) and 1.82 eV for Sb(2)Se(3), respectively. The optimal reaction conditions for the growth of bulk tubular single crystals were that the temperature was not lower than 180 degrees C and the reaction time was not shorter than 7 days. The possible growth mechanism of tubular crystals was also discussed.     

Microwave-assisted synthesis of sulfide M2S3 (m = Bi, Sb) nanorods using an ionic liquid

Single-crystalline Bi(2)S(3) and Sb(2)S(3) nanorods have been successfully synthesized by the microwave-assisted ionic liquid method. The starting reagents were Bi(2)O(3) or Sb(2)O(3), HCl, Na(2)S(2)O(3), and ethylene glycol (EG) or ethanolamine, and the ionic liquid used was 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF(4)]). Our experiments showed that the ionic liquid played an important role in the morphology of M(2)S(3) (M = Bi, Sb). Single-crystalline Bi(2)S(3) nanorods could be prepared in the presence of [BMIM][BF(4)]. However, urchinlike Bi(2)S(3) structures consisting of nanorods were formed without using [BMIM][BF(4)]. Single-crystalline Sb(2)S(3) nanorods were obtained in the presence of [BMIM][BF(4)]. However, single-crystalline Sb(2)S(3) nanosheets could be prepared in the absence of [BMIM][BF(4)]. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and electron diffraction (ED).     

Polynuclear cobalt(II/III) sulfites: synthesis, structure, and magnetic properties of the octanuclear cluster (NH4)11(Li subset[Co4IICo4III(SO3)16(NH3)8]).10H2O encapsulating a lithium cation

Partial oxidation of an aqueous solution of CoIICl(2).6H2O with (NH4)6[Mo7VIO24].4H2O in the presence of (NH4)2SO3.H2O and LiCl, at pH approximately 5.3, leads to isolation of the octanuclear cluster (NH4)11(Li subset[Co4IICo4III(SO3)16(NH3)8].10H2O), 1. The structure of the anion of 1 consists of a central [Co4II], almost ideal square planar unit, and a pair of symmetry-related CoIII dimers above and below the Co4II plane grafting onto the tetramer by 16 bridging sulfite groups. The [Co8(SO3)16(NH3)8]12- cluster encapsulates a lithium cation which lies at the center of the Co4II square.