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.     

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.     

Gas-phase measurements of the surface basicity of AlPO4?TiO2 and AlPO4?ZrO2 catalysts

The amount and strength of basic sites of AlPO₄–TiO₂ and AlPO₄–ZrO₂ catalysts over a different range of AlPO₄/metal oxide weight ratios were measured by studying the adsorption of acid molecules (acrylic acid and phenol) in the gas phase (473–673 K) by using the gas-chromatographic pulse method. The results obtained show that the basicity of AlPO₄–TiO₂ and AlPO₄–ZrO₂ catalysts is far lower than that of pure AlPO₄, and with an increase in the metal oxide (TiO₂ or ZrO₂) weight ratio, the basicity decreases. Besides, the basicity of AlPO₄–ZrO₂ is fairly low compared with that AlPO₄–TiO₂. In both cases, the total basicity (measured at 473 K vs. acrylic acid) gradually decreases with the calcination temperature while the stronger basic sites (measured at 573 K vs. phenol) remained unchanged up to calcination temperatures of 1073 K. Some weak surface basic sites remained in catalysts pretreated at 1273 K.

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- AlPO₄–TiO₂ AlPO₄–ZrO₂ AlPO₄/ , ( ) (473–673 K). , AlPO₄–TiO₂ AlPO₄–ZrO₂ AlPO₄ TiO₂ ZrO₂. , AlPO₄–ZrO₂ AlPO₄–TiO₂. — 473 K — , , 573 K , 1073 K. , 1273 K, .

     

Cr2(WO4)3和Cr2(MoO4)3的负热膨胀特性研究

用液相反应-前驱物烧结法制备了Cr₂(WO₄)₃和Cr₂(MoO₄)₃粉体。298～1 073 K的原位粉末X射线衍射数据表明Cr₂(WO₄)₃和Cr₂(MoO₄)₃的晶胞体积随温度的升高而增大, 本征线热膨胀系数分别为(1.274±0.003)×10^-6 K^-1和(1.612±0.003)×10^-6 K^-1。用热膨胀仪研究了Cr₂(WO₄)₃和Cr₂(MoO₄)₃在静态空气中298～1 073 K范围内热膨胀行为，即开始表现为正热膨胀，随后在相转变点达到最大值，最后表现为负热膨胀，其负热膨胀系数分别为(-7.033±0.014)×10^-6 K^-1和(-9.282±0.019)×10^-6 K^-1。     

Crystal structure of a tetrahedral cluster complex [Zn2(NH3)6(μ-OH)][Zn(NH3)4]0.5[Re4Te4(CN)12]·5H2O

A cluster complex of the composition [Zn₂(NH₃)₆(μ-OH)][Zn(NH₃)₄]_0.5[Re₄Te₄(CN)₁₂]·5H₂O is obtained by the interaction of an aqueous solution of K₄[Re₄Te₄(CN)₁₂]·5H₂O with an aqueous ammonia solution of ZnCl₂. The compound crystallizes in the C2/m (12) monoclinic space group with unit cell parameters a = 23.233(2) ?, b = 14.5906(16) ?, c = 14.3825(15) ?, β = 125.169(1)°, V = 3985.5(7) ?³, Z = 4, d _x = 3.290 g/cm³. The structure is built from cluster [Re₄Te₄(CN)₁₂]⁴⁻ anions and complex [Zn₂(NH₃)₆(μ-OH)]³⁺ and [Zn(NH₃)₄]²⁺ cations; the latter is disordered over two positions.     

Synthesis and characterization of a new octamolybdate (NH4)4[Mo8O24(C3H2O2)2] · 4H2O

A new complex with the formula (NH₄)₄[Mo₈O₂₄(C₃H₂O₂)₂] · 4H₂O (1) has been synthesized and characterized by single crystal X-ray diffraction and infrared spectrum. The complex is small yellow crystal and space group P ₁ with a = 9.9869(18) ?, b = 10.030(19) ?, c = 10.366(19) ?, α = 91.68(3)°, β = 98.94(3)°, γ = 119.37(2)°, V = 887(3) ?³, and Z = 1. The complex contains two malonic acid ligands bonded to the γ-Mo_{8 26}⁴⁻ ions which consist of eight MoO₆ edge-sharing octahedral. In this crystal structure, the octamolybdate anion is mutually hydrogen bonded by ammonium ions and water molecules.     

Stability and thermal behaviour of BH4-anions inside pores of sodium-potassium-tetrahydroborate aluminosilicate sodalite (Na1?x Kx)8[AlSiO4]6(BH4)2; x?~?0.5

Tetrahydroborate enclathrated sodalites are interesting compounds which offer new concepts for hydrogen storage as well as possibilities of special chemical reactions inside pores by the strong reduction force of tetrahydroborate. In the present paper, we show that these new materials can be further modified by hydrothermal cation exchange without decomposition of the predominant amounts of the hydrolysis sensitive BH₄ ⁻ anions inside the sodalite cages. We succeeded in preparing sodalite (Na_1−x K_x)₈[AlSiO₄]₆(BH₄)₂; (x ~ 0.5) by hydrothermal treatment of the pure sodium tetrahydroborate sodalite in KNO₃-solution at 473 K for 48 h. This product was characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and temperature dependent FT-IR-spectroscopy. Investigations of thermal reaction behaviour of the enclathrated BH₄ ⁻ anions revealed a decrease in metaborate formation temperature close to 100 K compared with the pure sodium tetrahydroborate sodalite. This is discussed by structural changes according to potassium incorporation and the influence of degradation of crystallinity during cation exchange.     

{[Cu4(nip)4(4，4′-bipy)4(DMF)4]·CH3OH}n配合物的合成与晶体结构

A coordination polymer, {[Cu₄(nip)₄(4，4′-bipy)₄(DMF)₄]·CH₃OH}_n, have been synthesized by the layer method using 5-nitroisophthalic acid (H₂nip), Cu(CH₃COOH)₂ and 4,4′-bipyridine(4,4′-bipy) with three solutions in a marrow tube and structurally characterized by X-ray single-crystal structure analysis. The results indicated that the nip ligand has a μ₂ mono-atomic bridging-monodentate coordination mode and the structure is a two-dimensional network. CCDC: 623420.     

Complex potassium yttrium molybdate phosphates K2Y1 ? xEux(MoO4)(PO4)0.9(VO4)0.1: Synthesis and study of luminescent properties

Samples with various dopant contents were obtained using solid-state and sol-gel methods. The resulting single-phase samples have the formula K₂Y_{1 − x} Eu _x (MoO₄)(PO₄)_0.9(VO₄)_0.1 (x = 0, 0.005, 0.01, 0.02, 0.03) and are isostructural with K₂Y(MoO₄)(PO₄). The possibility of formation of complex molybdate vanadates M₂^IM^III(MoO₄)(VO₄). was studied. Unlike their precursor K₂Y(MoO₄)(PO₄), the complex potassium yttrium molybdate phosphates obtained are deliquescent. Their structures contain no water molecules. The absorption and emission spectra of the compounds under study were recorded. In all the spectra, the electric dipole transition ⁵ D ₀−⁷ F ₂ (616 nm) is appreciably more intense than the magnetic dipole transition ⁵ D ₀−⁷ F ₁ (590 nm). This suggests that the coordination environment of the Eu³⁺ ion keeps asymmetric. The excitedstate lifetimes of anhydrous and humidified samples were determined. The average lifetime is the same for all samples (≈1.5 ms), which is due to the stability of their structures.     

Synthesis and study of the properties of K2Y1 ? x ? yEuxTby(MoO4)(PO4) and K2Y1 ? x ? yEuxTby(MoO4)(PO4)1?δ(VO4)δ solid solutions

Al synthesized samples are isostructural and crystallize in the orthorhombic symmetry system, space group Ibca. Particles of the final product of ∼200 nm in size have been obtained. The introduction of the vanadate anion into the matrix composition leads to the lowering of the symmetry of the Eu³⁺ environment and to the rise of the defect luminescence at 450–550 nm because of the unit cell distortion. The luminescence of defects in terbium-europium-containing samples is determined by the sample surface area, which decreases on annealing. The τ, W ₀ and γ parameters of the luminescence kinetics of the samples have been determined.     

四核铁配合物[Fe4(NTB)4(μ2-O)2(μ4-Suc)](ClO4)6促进DNA水解

四核铁配合物[Fe₄(NTB)₄(μ₂-O)₂(μ₄-Suc)](ClO₄)₆与DNA具有较强的结合作用，结合常数k_{b达(5.9±0.4)×10⁵ L·mol^-1。该多核铁配合物由水解途径促进DNA断裂，在酸性及低离子浓度条件下的促进作用较为显著。动力学分析表明DNA水解没有明显的序列选择性，质粒DNA从超螺旋转变为切口形式符合饱和酶动力学规律，饱和速率常数ksat=0.014 min^-1。}     

Synthesis and crystal structure of new one-dimensional copper(II) complex [Cu4(En)2(μ1,1-N3)4(μ1,1,1-N3)2(μ1,3-N3)2]n

A new polymer azido-bridged copper(II) complex [Cu₄(En)₂(μ_1,1-N₃)₄(μ_1,1,1-N₃)₂(μ_1,3-N₃)₂] _n (I) (En = ethylenediamine) has been synthesized and crystallography characterized. Complex I shows one-dimensional coordination polymeric structure based on a tetranuclear cluster unit [Cu₄(En)₂(μ_1,1-N₃)₄(μ_1,1,1-N₃)₂(μ_1,3-N₃)₂], in which the azido ions display three different bridging modes.     

Synthesis and crystal structure of (C3N5H6S)2[UO2(C2O4)2(H2O)] · C2N4H4

The formation of the thioammelinium cation in an aqueous solution in the presence of uranyl ions is demonstrated. Single crystal X-ray diffraction study of (C₃N₅H₆S)₂[UO₂(C₂O₄)₂(H₂O)] · C₂N₄H₄ was carried out and the geometric characteristics of thioammelinium were determined for the first time. The crystals are triclinc, space group , Z = 2, a = 8.5201(11) ?, b = 11.4027(14) ?, c = 14.329(2) ?, α = 103.182(5)°, β = 99.607(6)°, γ = 109.698(4)°, R = 0.0526. The main structural units in the crystal are mononuclear complex groups [UO₂(C₂O₄)₂(H₂O)]²⁻ corresponding to the crystal chemical group AB ₂ ⁰¹ M¹ (A = UO ₂ ²⁺ , B⁰¹ = C₂O ₄ ²⁻ , M¹ = H₂O) of uranyl complexes. Uranium-containing mononuclear complexes are connected into a three-dimensional framework through electrostatic interactions and hydrogen bonds involving thioammelinium ions, water molecules, and cyanoguanidine. Original Russian Text ? L.B. Serezhkina, A.V. Virovets, E.V. Peresypkina, I.V. Medrish, 2007, published in Koordinatsionnaya Khimiya, 2007, Vol. 33, No. 5, pp. 380–385.     

Specifics of pyrohydrolytic and solid-phase syntheses of solid solutions in the (MgGa2O4)x(MgFe2O4)1 ? x system

This work demonstrates the possibility of preparing solid solutions in the (MgGa₂O₄) _x (MgFe₂O₄)_{1 − x} system by pyrohydrolytic and solid-phase methods. It is shown that the products obtained have different specific surface areas depending on the ratio between metal nitrates and citric acid. The composition dependence of the unit cell parameter deviates considerably from the Vegard’s rule. The compounds obtained are found to be stable up to 300°C, which makes them candidate materials for electronics.     

Synthesis and crystal structure of [W3S4(Acac)3(PPh3)3]PF6 · 0.5CHCl3 and [W3S4(Hfac)3(PPh3)2Br] · 2CHCl3

New cluster complexes [W₃S₄(Acac)₃(PPh₃)₃]PF₆ · 0.5CHCl₃ (Acac = CH₃C(O)CHC(O)CH₃) (I) and [W₃S₄(Hfac)₃(PPh₃)₂Br] · 2CHCl₃ (Hfac = CF₃C(O)CHC(O)CF₃) (II) were synthesized. Their molecular and crystal structures were determined by X-ray diffraction. The cis-cis type of coordination of acetylacetonate and hexafluoroacetylacetonate ligands in I and II, respectively, was established, and the PPh₃ ligands were found in the trans-positions with respect to the “capping” sulfide ligand (μ³-S).     

Aldol condensation reactions of [Co(η-C4Ph4){η-C5H4C(O)CH3}]

The aldol condensation reaction between [Co(η⁴-C₄Ph₄){η⁵-C₅H₄C(O)CH₃}] and a range of aromatic aldehydes [RCHO] and [RCHCH-CHO] gives a series of α,β-unsaturated ketones [Co(η⁴-C₄Ph₄){η⁵-C₅H₄C(O)CHCH-R}] and [Co(η⁴-C₄Ph₄){η⁵-C₅H₄C(O)CHCH-CHCH-R}] (3). The reaction is promoted by various bases: NaH proved to be the most effective whilst ⁿBuLi gave [Co(η⁴-C₄Ph₄){η⁵-C₅H₄C(OH)(ⁿBu)CH₃}] as the major product. NaOH was ineffective, perhaps indicating that that the methyl protons in [Co(η⁴-C₄Ph₄){η⁵-C₅H₄C(O)CH₃}] are less acidic than those in [Fe(η⁵-C₅H₅){η⁵-C₅H₄C(O)CH₃}]. Compounds 3 were characterised spectroscopically. Their ¹H NMR spectra are consistent with a trans configuration about their CC bond, and this was confirmed by X-ray crystallography in five cases, which showed that all have the same basic structure with parallel cyclobutadiene and cyclopentadienyl ligands, but they are not identical. The C₅H₄C(O)(CHCH)_n-R (n = 1 or 2) moieties show little evidence for delocalisation and often deviate from planarity. The UV/Vis spectra of those 3 with smaller aromatic rings (R = C₆H₅, 4-C₆H₄NMe₂, 2-C₄H₃S and 1-C₁₀H₇) suggest that these are donor-π-acceptor systems, but as the annellation of R increases (R = 9-C₁₄H₉, 1-C₁₆H₉ and 1-C₂₀H₁₁) the spectra increasingly resemble those of the parent polycyclic aromatic hydrocarbon, RH. Reduction of [Co(η⁴-C₄Ph₄){η⁵-C₅H₄C(O)CHCH-C₁₀H₇-1}] with DIBAL gives a mixture of [Co(η⁴-C₄Ph₄){η⁵-C₅H₄C(O)CH₂CH₂-C₁₀H₇-1}] and [Co(η⁴-C₄Ph₄){η⁵-C₅H₄CH(OH)CHCH-C₁₀H₇-1}]. A minor product from the preparation of [Co(η⁴-C₄Ph₄){η⁵-C₅H₄C(O)CH₃}] was shown by X-ray crystallography to be the η⁴-butadiene complex [Co{η⁴-Ph(H)CC(Ph)-C(Ph)C(H)Ph}{η⁵-C₅H₄C(O)CH₃}].     

[Pt2(P2O4H2)4]4-和[Pt2(P2O4CH4)4]4-基态和激发态性质的理论研究

采用从头计算MP2和CIS方法分别优化等电子双核d⁸配合物[Pt₂(P₂O₄H₂)₄]^4-和[Pt₂(P₂O₄CH₄)₄]^4-的基态和激发态结构。结果表明基态Pt-Pt距离分别为0.290 5和0.298 7 nm，与实验的0.292 5和0.298 0 nm符合。NBO计算的Pt-Pt键级以及Pt原子间伸缩振动说明Pt-Pt相互作用具有吸引本质。CIS计算揭示电子激发到Pt-Pt的σ(p_z)成键轨道使得相互作用增强。保持激发态几何，含时密度泛函理论(TD-DFT)计算的溶液发射分别为449和475 nm，与实验值512和510 nm接近。     

水系混合离子全电池LiMn2O4//NaTi2(PO4)3

分别以LiMn_2O_4,NaTi_2(PO_4)_3为正负极,1 mol·L~(-1) Li_2SO_4和0.5 mol·L~(-1) Na_2SO_4的混合水溶液为电解液组装成一种水系混合离子全电池。分别将正负极材料在3种不同水相电解液(1 mol·L~(-1) Li_2SO_4、0.5 mol·L~(-1)Na_2SO_4以及1 mol·L~(-1) Li_2SO_4+0.5 mol·L~(-1)Na_2SO_4混合电解液)中进行循环伏安和恒流充放电测试,结果发现,LiMn_2O_4在上述电解液中仅有Li~+的脱出/嵌入而Na~+由于半径较大而不参与该过程,NaTi_2(PO_4)_3在3种电解液中Li+、Na+均参与嵌入/脱嵌过程,且Li~+和Na~+的嵌入/脱出峰电位相差不大,分别为-0.82和-0.64 V,-0.95和-0.75 V;全电池在265 mA·g~(-1)电流密度下平均放电电压为1.55 V,充放电比容量分别为100.1和74.9 m Ah·g~(-1)。     

The crystal structure of Yb2(SO4)3·3H2O and its decomposition product, β-Yb2(SO4)3

Yb₂(SO₄)₃·3H₂O, synthesised by hydrothermal methods at 220(2) °C, has been investigated by single crystal X-ray diffraction. Yb₂(SO₄)₃·3H₂O crystallises in space group Cmc2₁ and is isostructural with Lu₂(SO₄)₃·3H₂O. The crystal structure has been refined to R₁=0.0145 for 3412 reflections [F_o>3σ(F)], and 0.0150 for all 3472 reflections. The structure of Yb₂(SO₄)₃·3H₂O is a complex framework of YbO₆ octahedra, YbO₈ and YbO₅(H₂O)₃ polyhedra and SO₄ tetrahedra. Thermal data shows that Yb₂(SO₄)₃·3H₂O decomposes between 120 and 190 °C to form β-Yb₂(SO₄)₃. The structure of a twinned crystal of β-Yb₂(SO₄)₃ was solved and refined using an amplimode refinement in R3c with an R₁=0.0755 for 8944 reflections [F_o>3σ(F)], and 0.1483 for all 16,361 reflections. β-Yb₂(SO₄)₃ has a unique structural topology based on a 3D network of pinwheels.