Crystal structures of seven-coordinate (NH4)2[MnII(edta)(H2O)]·3H2O, (NH4)2[MnII(cydta)(H2O)]·4H2O and K2[MNII(hdtpa)]·3.5H2O complexes

The title compounds, (NH₄)₂[Mn^II(edta)(H₂O)]·3H₂O (H₄edta = ethylenediamine-N,N,N′,N′-tetraacetic acid), (NH₄)₂[Mn^II(cydta)(H₂O)]·4H₂O (H₄cydta = trans-1,2-cyclohexanediamine-N,N,N′,N′-tetraacetic acid) and K₂[Mn^II(Hdtpa)]·3.5H₂O (H₅dtpa = diethylenetriamine-N,N,N′,N″,N″-pentaacetic acid), were prepared; their compositions and structures were determined by elemental analysis and single-crystal X-ray diffraction technique. In these three complexes, the Mn²⁺ ions are all seven-coordinated and have a pseudomonocapped trigonal prismatic configuration. All the three complexes crystallize in triclinic system in P-1 space group. Crystal data: (NH₄)₂[Mn^II(edta)(H₂O)]·3H₂O complex, a = 8.774(3) ?, b = 9.007(3) ?, c = 13.483(4) ?, α = 80.095(4)°, β = 80.708(4)°, γ = 68.770(4)°, V = 972.6(5) ?³, Z = 2, D _c = 1.541 g/cm³, μ = 0.745 mm⁻¹, R = 0.033 and wR = 0.099 for 3406 observed reflections with I ≥ 2σ(I); (NH₄)₂[Mn^II(cydta)(H₂O)]·4H₂O complex, a = 8.9720(18) ?, b = 9.4380(19) ?, c = 14.931(3) ?, α = 76.99(3)°, β = 83.27(3)°, γ = 75.62(3)°, V = 1190.8(4)?³, Z = 2, D _c = 1.426 g/cm³, μ = 0.625 mm⁻¹, R = 0.061 and wR = 0.197 for 3240 observed reflections with I ≥ 2σ(I); K₂[Mn^II(Hdtpa)]·3.5H₂O complex, a = 8.672(3) ?, b = 9.059(3) ?, c = 15.074(6) ?, α = 95.813(6)°, β = 96.665(6)°, γ = 99.212(6)°, V = 1152.4(7) ?³, Z = 2, D _c = 1.687 g/cm³, μ = 1.006 mm⁻¹, R = 0.037 and wR = 0.090 for 4654 observed reflections with I ≥ 2σ(I). Original Russian Text Copyright ? 2008 by X. F. Wang, J. Gao, J. Wang, Zh. H. Zhang, Y. F. Wang, L. J. Chen, W. Sun, and X. D. Zhang The text was submitted by the authors in English. Zhurnal Strukturnoi Khimii, Vol. 49, No. 4, pp. 753–759, July–August, 2008.     

［Mn2(CHZ)4(H2O)2］(PA)4·10H2O的制备和分子结构研究

本文论述了苦味酸(PA,三硝基苯酚)锰与碳酰肼(CHZ, NH₂NHCONHNH₂)反应制备目标配合物的方法及该配合物的晶体结构。该配合物的结构式为［O,O′-μ-Mn₂(CHZ)₄(H₂O₂)］(PA)₄·10H₂O。晶体属三斜晶系,P1 空间群。晶体学参数为：a=0.8269(1) nm, b=1.2812(1) nm, c=1.5915(1) nm; α=109.58(1)°, β=95.19(1)°, γ=92.76(1)°, V=1.5765(2)nm³; Z=1, Dc=1.580 g·cm^-3, μ(Mo K_α)=520 m^-1。晶体结构经全矩阵最小二乘法修正,最终偏离因子R=0.0557。该化合物为具有中心对称的双核配合物,以两个碳酰肼分子中羰基氧为桥原子将两个锰离子结合起来,与锰离子形成配位键的原子是碳酰肼分子第一、五氮原子,羰基氧原子和水分子中的氧原子,锰离子的配位数为七。若味酸根作为外界离子以库伦力和氢键与内界离子结合成配合物分子。     

Crystal structure of K2[Mo3(PdPPh3)S4(C2O4)3(H2O)3]·0.5H2O

By the reaction of [Mo₃S₄(C₂O₄)₃(H₂O)₃]²⁻ with PdCl₂ and NH₄H₂PO₂ as a reducing agent, followed by the addition of PPh₃, a new oxalate cuboidal cluster complex [Mo₃(PdPPh₃)S₄(C₂O₄)₃(H₂O)₃]²⁻ is obtained. It was isolated and structurally characterized as K₂[Mo₃(PdPPh₃)S₄(C₂O₄)₃(H₂O)₃]·0.5H₂O. Original Russian Text Copyright ? 2008 by A. L. Gushchin, M. N. Sokolov, D. Yu. Naumov, and V. P. Fedin __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 4, pp. 775–778, May–June, 2008.     

Synthesis and crystal structure of [Na2(μ-H2O)(H2O)CB[5]]Cl2 · 6H2O, [Na3(μ-H2O)4(H2O)4(CNPy@CB[6])]Cl3 · 8H2O, and [Rb2(μ-H2O)2(CNPy@CB[6])]Cl · 8H2O

The chain coordination polymers [Na₂(μ-H₂O)(H₂O)CB[5]]Cl₂ · 6H₂O (I), [Na₃(μ-H₂O)₄(H₂O)₄(CNPy@CB[6])]Cl₃ · 8H₂O (II), and [Rb₂(μ-H₂O)₂(CNPy@CB[6])]Cl₂ · 8H₂O (III) were prepared by heating (110°C) of a mixture of sodium or rubidium chloride, cucurbit[n]uril (CB[n], where n = 5, 6), 4-cyanopyridine, and water. According to X-ray diffraction data, binding of polynuclear cations with CB[n] in I–III occurs through coordination of the oxygen atoms of the cucurbit[n]uril portals to alkali metal atoms. Complexes I–III of the above composition isolated to the solid phase as supramolecular compounds with CB[n] were structurally characterized for the first time.     

Synthesis, structure, and physicochemical properties of K[VO2(SeO4)(H2O)] and K[VO2(SeO4)(H2O)2] · H2O

The vanadium(V) complexes K[VO₂(SeO₄)(H₂O)] and K[VO₂(SeO₄)(H₂O)₂] · H₂O were synthesized using original procedures; their physicochemical properties were studied, and the crystal structure was determined on the basis of X-ray diffraction and neutron diffraction data. The structure of K[VO₂(SeO₄)(H₂O)₂] · H₂O is composed of VO₆ octahedra connected to form infinite chains by bridging SeO₄ tetrahedra. Each VO₆ tetrahedron has short terminal V-O bonds forming the bent dioxovanadium group VO₂⁺ The unit cell parameters of K[VO₂(SeO₄)(H₂O)₂] · H₂O are a = 6.4045(1) ?, b = 9.9721(2) ?, c = 6.6104(1) ?, β = 107.183(1)°, V = 403.34 ?³, Z = 2, monoclinic system, space group P2₁. The complex K[VO₂(SeO₄)(H₂O)] forms a two-dimensional layered structure composed of highly distorted VO₆ octahedra having two short terminal V-O bonds and SeO₄ groups coordinated simultaneously by three vanadium atoms. This compound crystallizes in the monoclinic system (space group P2₁/c): a = 7.3783(1) ?, b = 10.5550(2) ?, c = 10.3460(2) ?, β = 131.625(1)°, V = 602.894(5) ?³, Z= 4. The vibrational spectra of the studied compounds are fully consistent with their structural features.     

Syntheses of the eight-coordinate NH4[ErIII(Cydta)(H2O)2] · 4.5H2O and (NH4)2[Er 2III (Pdta)2(H2O)2] · 2H2O complexes and their structural investigation

In this work, the title complexes, NH₄[Er^III(Cydta)(H₂O)₂] · 4.5H₂O (I) (H₄Cydta = trans-1,2-cyclo-hexanediamine-N,N,N′,N′-tetraacetic acid) and (NH₄)₂[Er₂^III(Pdta)₂(H₂O)₂] · 2H₂O (II) (H₄Pdta= propylene-diamine-N,N,N′,N′-tetraacetic acid), were prepared, respectively, and their composition and structures were determined by elemental analyses and single-crystal X-ray diffraction techniques. Complex I selects a mononu-clear structure with pseudosquare antiprismatic geometry crystallized in the triclinic crystal system with space group $ P\bar 1 $ P\bar 1 and the central Er³⁺ ion is eight-coordinated by the hexadentate Cydta ligand and two water molecules. The crystal data are as follows: a = 8.568(3), b = 10.024(3), c = 14.377(4) ?, α = 88.404(4)°, β = 75.411(4)°, γ = 88.332(4)°, V = 1194.2(6) ?³, Z = 1, ρ _c = 1.793 g/cm³, μ = 3.586 mm⁻¹, F(000) = 648, R = 0.0257, and wR = 0.0667 for 4169 observed reflections with I ≥ 2σ(I). Complex II is eight-coordinated as well, which selects a binuclear structure with two pseudosquare antiprismatic geometry and crystallizes in the monoclinic crystal system with space group P2₁/n. The central Er³⁺ ion is coordinated by two nitrogens and four oxygens from one hexadentate Pdta ligand. Besides, two oxygens come from one carboxylic group of the neighboring Pdta ligand and one water molecule, respectively. The crystal data are as follows: a = 12.7576(8), b = 9.3151(6), c = 14.3278(9) ?, β = 96.1380(10)°, V = 1692.93(19) ?³, Z = 4, ρ _c = 2.054 g/cm³, μ = 5.015 mm⁻¹, F(000) = 1028, R= 0.0228, and wR = 0.0534 for 2984 observed reflections with I ≥ 2σ(I).     

N，N′-(2-苯并咪唑基甲基)亚氨基甲基膦酸的双核镍化合物Ni2(bbimp)2(4，4′-bipy)(H2O)2·2H2O和Ni2(bbimp)2(H2O)2][Ni(bbimp)(H2O)2]2·4H2O

该文报道了N，N′-(2-苯并咪唑基甲基)亚氨基甲基膦酸{bbimpH₂，[(C₇H₅N₂)CH₂]₂NCH₂PO₃H₂}的2个镍化合物Ni₂(bbimp)₂(4，4′-bipy)(H₂O)₂·2H₂O (1)和[Ni₂(bbimp)₂(H₂O)₂][Ni(bbimp)(H₂O)₂]₂·4H₂O (2)。化合物1是4，4′-联吡啶作为桥连配体的中性双核结构。化合物2含有1个中性的[Ni₂(bbimp)₂(H₂O)₂]双核分子与2个中性的[Ni(bbimp)(H₂O)₂]单核分子。双核分子单元中的2个Ni(Ⅱ)离子被2个膦酸氧桥连。在化合物2中，膦酸氧桥连的2个Ni(Ⅱ)离子之间存在铁磁性相互作用。     

Crystal structures of barium bis(iminodiacetato)cobaltates(III): [Ba(H2O)6][Co(Ida)2]2 · H2O and Ba4(H2O)14][Co(Ida)2]5(ClO4)3 · 5.46H2O · 2CH3OH

The structures of the crystals of Ba₄[trans(N)-Co(Ida)₂]₃[cis-(N)-Co(Ida)₂]₂(ClO₄)₃ · 19.46H₂O · 2CH₃OH (I) and Ba[trans-(N)-Co(Ida)₂]₂ · 7H₂O (II) (H₂Ida is iminodiacetic acid) were determin by X-ray diffraction. The crystals of I containing two geometric isomers of the complex anions [Co(Ida)₂]⁻ were obtained by a slow cooling of a hot solution, which contained initially only the cis-isomer. One Ba atom in I interacts with the trans-complex and with two cis-complexes to give a three-dimensional framework in crystal I. The positive charge of the last framework is compensated by one more trans-complex and by the perchlorate ions, one of which acts as a bidentate ligand with respect to the Ba atom. The crystals of II are built of the chains with the alternating Ba atoms and the trans-(N)-[Co(Ida)₂]⁻ anions. The other anions of the same structure are each “suspended” to the Ba atoms of the chain. Original Russian Text ? M. Zabel, A.I. Poznyak, V.I. Pawlowskii, 2008, published in Koordinatsionnaya Khimiya, 2008, Vol. 34, No. 11, pp. 831–836.     

Structural determination of new eight-coordinate NH4[EuIII(Cydta)(H2O)2]·4.5H2O and K2[Eu 2III (pdta)2(H2O)2]·6H2O complexes

The NH₄[Eu^III(Cydta)(H₂O)₂]·4.5H₂O (I) (H₄Cydta = trans-1,2-cyclohexanediamine-N,N,N′,N′-tetraacetic acid) and K₂[Eu₂^III(pdta)₂(H₂O)₂]·6H₂O (II) (H₄pdta = propylenediamine-N,N,N′,N′-tetraacetic acid) complexes are prepared by heat-refluxing and acidity-adjusting methods respectively, and their composition and structures are determined by elemental analyses and single crystal X-ray diffraction techniques. The complex I has a mononuclear structure, crystallizes in the triclinic crystal system with the P[`1]P\bar 1 space group; the central Eu^III ion is eight-coordinated by a hexadentate Cydta ligand and two water molecules. The crystal data are as follows: a = 8.653(4) ?, b = 10.041(4) ?, c = 14.405(6) ?, α = 88.469(6)°, β = 74.892(6)°, γ = 88.256(7)°, V = 1207.5(9) ?³, Z = 1, D _c = 1.731 g/cm³, μ = 2.669 mm⁻¹, F(000) = 638, R = 0.0257, and wR = 0.0667 for 3807 observed reflections with I ≥ 2σ(I). The EuN₂O₆ part in the [Eu^III(Cydta)(H₂O)₂]⁻ complex anion forms a pseudo-square antiprismatic polyhedron. The complex II is eight-coordinate as well; it is a binuclear structure that crystallizes in the monoclinic crystal system with the C ₂/c space group; half of the central Eu^III ion is coordinated by two nitrogen atoms from one hexadentate pdta ligand and six oxygen atoms from the same pdta ligand, one water molecule and carboxylic group from the neighboring pdta ligand respectively. The crystal data are as follows: a = 19.866(3) ?, b = 9.1017(12) ?, c = 21.010(3) ?, β = 104.972(2)°, V = 3670.1(9) ?³, Z = 8, D _c = 2.046 g/cm³, μ = 3.710 mm⁻¹, F(000) = 2240, R = 0.0213 and wR = 0.0460 for 4183 observed reflections with I ≥ 2σ(I). Otherwise, the two EuN₂O₆ parts in the [Eu₂^III(pdta)₂(H₂O)₂]²⁻ complex anion form a pseudo-square antiprismatic polyhedron.     

Synthesis, structure, and thermal decomposition of [H2(4,4′-Bipy)][In(H2O)2(NCS)4]2 and [HUr]2[In(H2O)(NCS)5] · 2H2O

The reaction of indium thiocyanate with bipyridine (4,4-Bipy) and urotropine (Ur) gave [H₂(4,4′-Bipy)][In(H₂O)₂(NCS)₄]₂ (I) and [HUr]₂[In(H₂O)(NCS)₅] · 2H₂O (II), which were identified using elemental analysis, IR spectra, and thermogravimetric analysis. The thermal decomposition of compound I and II ends at 650 and 640°C, respectively, and gives In₂O₃. X-Ray diffraction analysis of compound I showed that complex anions in the crystal form chains through O-H…S hydrogen bonds. The anion chains form a close packing of columns with bipyridine cations located in the voids. Original Russian Text ? S.P. Petrosyants, A.B. Ilyukhin, V.A. Ketsko, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 6, pp. 951–955.     

Synthesis and structures of nine-coordinate K[Dy(Edta)(H2O)3] · 3.5H2O, (NH4)3 [Dy(Ttha)] · 5H2O, and eight-coordinate NH4[Dy(Cydta)(H2O)2] · 4.5H2O complexes

The title complexes, K[Dy(Edta)(H₂O)₃] · 3.5 H₂O (I) (H₄Edta = ethylenediamine-N,N,N′,N′-tetraacetic acid), (NH₄)₃[Dy(Ttha)] · 5H₂O (II) (H₆Ttha = triethylenetetramine-N, N,N′,N″,N‴,N‴-hexaacetic acid), and NH₄[Dy(Cydta)(H₂O)₂] · 4.5H₂O (III) (H₄Cydta = trans-1,2-cyclohexanediamine-N,N,N′,N′-tetraacetic acid), were prepared, and their compositions and structures were determined by elemental analyses and single-crystal X-ray diffraction techniques, respectively. In complex I, the Dy³⁺ ion is nine-coordinated by an Edta ligand and three water molecules, yielding a pseudo-monocapped square antiprismatic conformation, and the complex crystallizes in the orthorhombic crystal system with space group Fdd2. The crystal data are as follows: a = 19.751(7), b = 35.573(12), c = 12.227(4) ?, V = 8591(5) ?³, Z = 16, space group Fdd2 ρ_c = 1.877 g/cm³, μ = 3.742 mm⁻¹, F(000) = 4800, R = 0.0259, and wR = 0.0616 for 3218 observed reflections with I ≥ 2σ(I). For complex II, the Dy³⁺ ion is nine-coordinated by a Ttha ligand, yielding a pseudo-monocapped square antiprismatic conformation, and the complex crystallizes in the monoclinic crystal system with space group P2₁/c. In addition, there is a free non-coordinate carboxyl group (-CH₂COO⁻) in the [Dy(Ttha)]³⁻ complex anion. The crystal data are as follows: a = 10.353(3), b = 12.746(4), c = 23.141(7) ?, β = 91.005(5)°, V = 3053.2(15) ?³, Z = 4, space group P2₁/c ρ_c = 1.730 g/cm³, μ = 2.532 mm⁻¹, F(000) = 1620, R = 0.0332 and wR = 0.0924 for 5390 observed reflections with I ≥ 2σ(I). For complex III, the Dy³⁺ ion is eight-coordinated by a ligand Cydta and two water molecules, yielding a distorted square antiprismatic conformation, and the complex crystallizes in the triclinic system with space group P . The crystal data are as follows: a = 8.604(3), b = 10.012(4), c = 14.369(6) ?, α = 88.330(6)°, β = 75.363(6)°, γ = 88.285(6)°, space group P V = 1196.9(8) ?³, Z = 2, ρ_c = 1.776 g/cm³, μ = 3.194 mm⁻¹, F(000) = 644, R = 0.0445 and wR = 0.1041 for 3931 observed reflections with I ≥ 2σ(I). The article is published in the original.     

[Gd2(Gly)6(H2O)4](ClO4)6(H2O)5的合成、晶体结构与热化学研究

利用微波技术合成了配合物[Gd₂(Gly)₆(H₂O)₄](ClO₄)₆(H₂O)₅, 进行了化学成分分析、红外表征和热重分析. 应用X衍射仪测定其晶体结构, 该晶体为一维链结构, 属三斜晶系, P 空间群, 晶胞参数: a＝1.1569(17) nm, b＝1.4138(2) nm, c＝1.5642(2) nm, α＝96.910(2)°, β＝102.735(2)°, γ＝105.512(2)°, V＝2.3606(6) nm³, Z＝2, D_c＝2.144 g•cm^－3. 采用精密溶解-反应量热计, 通过设计热化学循环, 计算出了该配合物的标准摩尔生成焓为 －(7960.73±3.23) kJ•mol^－1.     

[Pb2(TNR)2(CHZ)2(H2O)2]·4H2O和[Cd(CHZ)2(TNR)(H2O)]快速热分解过程的研究

利用温度跃升傅立叶变换红外原位分析技术在0.1MPa氩气的条件下，对斯蒂酚酸碳酰肼铅和斯蒂酚酸碳酰肼镉的快速热分解过程进行了研究。研究结果表明，斯蒂酚酸碳酰肼铅的主要热分解气体为NH₃, H₂O和 HONO，而斯蒂酚酸碳酰肼镉的主要热分解气体为CO 和 NO，因此斯蒂酚酸碳酰肼镉不满足作为环境友好起爆药的使用要求。这两种化合物在快速热分解过程中均产生金属异氰酸盐、金属碳酸盐和金属氧化物。利用Real程序计算其燃烧温度可得斯蒂酚酸碳酰肼铅的燃烧温度要高于斯蒂酚酸碳酰肼镉，对其燃烧产物进行计算，发现HNCO不在燃烧产物之列，NO的含量也比实验得出的浓度要小。     

Heat capacity and thermodynamical properties of the crystal of [RE2(Glu)2(H2O)8](ClO4)4·H2O (RE = Nd, Eu, Dy)

Thermodynamical data of rare earth complexes with amino acid are important for engineering chemistry and fundamental chemistry. However, they have rarely been reported. In this work, a series of crystalline complexes of rare earth perchlorate coordinated with glutamic acid have been synthesized in water medium, and their thermodynamical data, including the heat capacity in low temperature range and the standard enthalpy of formation, were determined. These complexes were identified to be [RE₂(Glu)₂(H₂O)₈](ClO₄)₄·H₂O (RE = Nd, Eu, Dy) by using thermogravimetric analysis (TG), differential thermal analysis (DTA), and chemical and elementary analyses. Their purity has been determined. No melting points were observed for all the three complexes. The heat capacity of the complexes was measured by an adiabatic calorimeter from 79 to 370 K. Abnormal heat capacity values were detected for two of the complexes and the decomposition range of one complex was found. The temperature, enthalpy change and entropy change of the decomposition processes of the three complexes were calculated. The polynomial equations of heat capacity in the experimental temperature range have been obtained by least squares fitting. The standard enthalpy of formation was determined by an isoperibol reaction calorimeter at 298.15 K. Supported by the Research Fund of Beijing Institute of Petro-Chemical Technology (N06-06)     

配合物Fe(pda)2(H2O)4和[FeCo(pda)4(H2O)4]n的合成与晶体结构

采用水热法合成了2个3-(3-吡啶基)丙烯酸的配合物:Fe(pda)2(H2O)4(1)和[FeCo(pda)4(H2O)4]n(2)(pda=3-(3-吡啶基)丙烯酸),用红外光谱、元素分析、热重-差热以及X-射线衍射单晶结构分析进行了表征.2个配合物都属于单斜晶系,配合物1的空间群为P21/n,配合物2的为P21/c.配合物1是一个pda配体中仅吡啶基氮原子参与配位、而羧基上的氧原子未参与配位的单核结构,通过大量的氢键作用形成三维超分子体系.2是pda配体桥联Fe和Co的异核二维层状配位聚合物;配体吡啶基上的氮原子和羧基上的氧原子都参与了配位,其中羧基采用单齿配位模式.     

Synthesis and crystal structure of [Fe4O2(H2O)10(C5H5NCOO)4](NO3)8 · 2H2O

Crystals of the tetranuclear complex [Fe₄O₂(H₂O)₁₀(C₅H₅NCOO)₄](NO₃)₈ · 2H₂O are obtained by the slow evaporation of an aqueous solution of iron(III) nitrate and isonicotinic acid. According to the X-ray diffraction data, four metal atoms lie in the same plane and together with two μ₃-O oxygen atoms form the fragment [Fe₄(μ₃-O)₂]¹⁰⁺. The [Fe₄O₂(H₂O)₁₀(C₅H₅NCOO)₄]⁸⁺ cation has been obtained and structurally characterized for the first time.     

Synthesis and structures of Cs4[(UO2)2(C2O4)(SO4)2(NCS)2] · 4H2O and (NH4)4[(UO2)2(C2O4)(SO4)2(NCS)2] · 6H2O

Single crystals of Cs₄[(UO₂)₂(C₂O₄)(SO₄)₂(NCS)₂] · 4H₂O (I) and (NH₄)₄[(UO₂)₂(C₂O₄)(SO₄)₂(NCS)₂] · 6H₂O (II) have been synthesized and studied by X-ray diffraction. The crystals of both compounds are orthorhombic with the space group Pbam, Z = 2, and unit cell parameters a = 12.0177(3) ?, b = 18.6182(5) ?, c = 6.7573(10) ?, R = 0.0376 (I); a = 11.6539(9) ?, b = 18.3791(13) ?, c = 6.7216(5) ?, R = 0.0179 (II). The main structural units of crystals I and II are [(UO₂)₂(C₂O₄)(SO₄)₂(NCS)₂]⁴⁻ chains belonging to the crystal-chemical group A₂K⁰²B₂²M₂¹ (A = UO₂²⁺, K⁰² = C₂O₄²⁻, B² = SO₄²⁻, M¹ = NCS⁻) of the uranyl complexes. The uranium-containing chains are joined into a three-dimensional framework due to a system of electrostatic interactions with the cesium or ammonium ions in the structure of I. In the structure of II, this framework is additionally stabilized by hydrogen bonds involving the outer-sphere water molecules and ammonium ions. Original Russian Text ? I.V. Medrish, A.V. Virovets, E.V. Peresypkina, L.B. Serezhkina, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 7, pp. 1115–1120.     

Synthesis and structures of nine-coordinate K[SmIII (Edta)(H2O)3] · 2H2O and Ten-Coordinate K2[SmIII(Pdta)(H2O)2]2 · 4.5H2O complexes

The title complexes, K[Sm^III(Edta)(H₂O)₃] · 2H₂O(I)(H₄Edta = ethylenediamine-N,N,N′,N′-tetraacetic acid) and K₂[Sm^III(Pdta)(H₂O)₂]₂ · 4.5H₂O (II) (H₄Pdta = propylenediamine-N,N,N′,N′-tetraacetic acid), were prepared and their compositions and structures were determined by elemental analyses and single-crystal X-ray diffraction techniques, respectively. Complex I has a mononuclear structure, and the Sm³⁺ ion is nine-coordinated by an Edta ligand and three water molecules, yielding a pseudo-monocapped square antiprismatic conformation, and the complex crystallizes in the orthorhombic crystal system with space group Fdd2. The crystal data are as follows: a = 19.84(5), b = 35.58(9), c = 12.15(3) ?, V = 8580(38) ?³, Z = 16, ρ _c = 1.925 g/cm³, μ = 3.010 mm⁻¹, F(000) = 4976, R = 0.0252, and wR = 0.0560 for 3510 observed reflections with I ≥ 2σ(I). Complex II has a binuclear structure and the Sm³⁺ ion is ten-coordinated by a Pdta ligand, two oxygen atoms from a carboxylic group of adjacent Pdta ligand and two water molecules, yielding a distorted bicapped square antiprismatic prism. The complex crystallizes in the triclinic crystal system with space group P $ \bar 1 $ \bar 1 . The crystal data are as follows: a = 8.9523(15), b = 10.7106(15), c = 11.6900(19) ?, α = 80.613(5)°, β = 80.397(5)°, γ = 76.530(4)°, V = 1065.7(3) ?³, Z = 1, ρc = 1.970 g/cm³, μ = 2.532 mm⁻¹, F(000) = 1620, R = 0.0332 and wR = 0.0924 for 5390 observed reflections with I ≥ 2σ(I).     

Formation of Co nanoparticles in the process of thermal decomposition of the cobalt complex with hexamethylenetetramine (NO3)2Co(H2O)6(HMTA)2 · 4(H2O)

The thermal decomposition of the cobalt complex with hexamethylenetetramine (NO₃)₂Co(H₂O)₆(HMTA)₂ · 4(H₂O) was studied by the methods of differential thermal analysis, thermogravimetry, mass spectrometry, X-ray diffraction analysis, and by the magnetic method. It was established that the thermal decomposition of the complex in a current of an inert gas is accompanied by a pronounced exothermic process and formation of Co nanoparticles. It was shown that the kinetics of this process and the chemical nature of the decomposition products depend on the initial density of the sample under study.