Synthesis and crystal structure of K3[NpO4(OH)2]

Attempts were made to isolate anhydrous compounds of [NpO₄(OH)₂]^3? anions with heavy alkali metal cations (K, Rb, Cs) by crystallization at elevated temperatures, and the salt K₃[NpO₄(OH)₂] was isolated and studied. Crystals of K₃[NpO₄(OH)₂] consist of tetragonal bipyramidal [NpO₄(OH)₂]^3? anions and K⁺ cations. The [NpO₄(OH)₂]^3? anion occupies the position in the symmetry center. The Np-O distances in this anion are 1.8992(7) and 1.9100(7) Å in the equatorial plane of the bipyramid and 2.3231(8) Å with OH groups. The OH hydrogen atoms participate in weak H bonds [O?O 3.0250(11) Å] linking the anions in layers [NpO₄(OH)₂] _n ^3n? parallel to the (010) plane. In the interlayer space, there are two crystallographically different K atoms. Their coordination number (CN) can be considered to be equal to 7 and 8. Comparison with the structures of the known compounds Na₃[NpO₄(OH)₂] and K₃[NpO₄(OH)₂]·2H₂O was made. The structure of the latter compound was redetermined with higher accuracy. The failure of attempts to prepare the anhydrous rubidium and cesium compounds is probably due to large ionic radius of these cations, requiring high coordination number.     

[Ag(PPh_3)_2(CH_3COO)]_2·3H_2O的合成和晶体结构

将醋酸银和三苯基磷按1∶2摩尔比例进行反应得到化合物Ag(PPh3)2(CH3COO)]2,采用红外光谱、核磁共振、元素分析和单晶X射线衍射的方法,对其结构进行了表征.晶体结构解析结果显示,配合物属单斜晶系,空间群C2/c,a=44.286 8',b=13.269 6',c=24.997 0',α=90.000°,β=105.573°,γ=90.000°,Z=8,R=0.052 0,wR2=0.132 4.     

Synthesis and Crystal Structure of the U(VI) Complex with Triphenylphosphine Oxide {UO2[OP(C6H5)3]4}(ClO4)2

Data on synthesis and structure of the U(VI) complex with triphenylphosphine oxide (TPPO) are presented. Single crystals were grown and the structure of this compound was determined [monoclinic unit cell: a = 9.795(3), b = 25.246(6), c = 14.086(4) Å, = 99.86(2)°, space group P2₁/c, Z = 2, V = 3431.7(15) ų, d _{c a l c} = 1.534 g cm^{- 3}; Siemens P3/PC, MoK radiation, graphite monochromator, /2thetas; scanning, 2947 unique reflections, direct method, R ₁ = 0.0401 for 2261 observed reflections, wR ₂ = 0.1194 for 2947 unique reflections]. The crystal structure consists of complex cations {UO₂[OP(C₆H₅)₃]₄}^{2 +} and ClO₄ ^- anions. The U(VI) atom has a tetragonal-bipyramidal oxygen surrounding with coordination number (CN) 6. The UO₂ group is linear: the O = U = O bond angle is 180.0°, and the U = O bond length is 1.750(6) Å. The square equatorial coordination plane of the bipyramid is formed by oxygen atoms of four TPPO molecules, the U-O_{e q} bond lengths vary from 2.289(6) to 2.307(6) Å (average 2.298 Å), and the O_{e q}-U-O_{e q} bond angles are close to 90°.     

Synthesis,Crystal Structure,and Spectral Characteristics of the Np(V) Complex with Triphenylphosphine Oxide [NpO2(PO(C6H5)3)4]ClO4

Single crystals of [NpO₂(PO(C₆H₅)₃)₄]ClO₄ were grown and the structure of this compound was studied (CAD4 diffractometer, MoK ; triclinic unit cell: a = 9.140(2), b = 13.528(3), c = 13.918(3) Å, = 97.14(3)°, = 108.17(3)°, = 91.75(3)°, space group P-1, Z = 1, V = 1618.0 ų, d _{c a l c} = 1.521 g cm^-3; R ₁ = 0.0245 for 5342 observed reflections with F ₀ > 4(F ₀), wR ₂ = 0.0677 for 5601 unique reflections, 419 refined parameters). [NpO₂(PO(C₆H₅)₃)₄]ClO₄ consists of complex cations [NpO₂(PO(C₆H₅)₃)₄]⁺ and disordered ClO_4- anions. The Np(V) atom has tetragonal-bipyramidal oxygen surrounding with coordination number (CN) 6. The NpO₂ group is linear, the O = Np = O bond angle is 180.0°, and the Np = O bond length is 1.797(2) Å. The equatorial coordination plane of the bipyramid is formed by oxygen atoms of four triphenylphosphine oxide (TPPO) molecules. The Np-O_eq bond lengths vary from 2.434(2) to 2.442(2) Å (average 2.438 Å). The O_eq-Np-O_eq bond angle is close to the right angle (88.98°). The average bond lengths in TPPO ligands are P-O 1.498, P-C 1.798, and C-C 1.376 Å; the average bond angles are O-P-O 111.12°, C-P-C 107.78°, P-C-C 120.2, and C-C-C 120.0°. The electronic absorption spectra (Shimadzu UV-3100, 900-1050 nm) and IR spectra (Specord-M80, 400-4000 cm^{- 1}) of crystalline [NpO₂(PO(C₆H₅)₃)₄] were measured in an NaCl matrix. The absence of the main characteristic absorption band of the NpO₂ ⁺ dioxocation (980 nm) in the electronic absorption spectrum suggests centrosymmetrical equatorial surrounding of the Np(V) atom. The narrow absorption band ta_{a s}(NpO₂ ⁺) in the IR spectra in the region of 860 cm^-1 suggests the absence of cation-cation interaction, and its position is consistent with a short Np-O bond length in neptunyl(V) groups.     

Synthesis and crystal structure refinement of Cu(I)Ti2(PO4)3

Single crystals of the Nasicon-type compound, Cu(I)Ti₂(PO₄)₃ were grown hydrothermally at 500°C under 3 kbar pressure. The crystal structure was solved by means of single crystal x-ray diffraction and refined to R = 0.027. Although the [Ti₂P₃O₁₂]⁻¹ framework in CuTi₂(PO₄)₃ is identical to Zr, P framwork in NaZr₂(PO₄)₃, the Cu atoms are shifted away from the M1 sites (3) occupied by Na in latter structure. The Cu atoms in CuTi₂(PO₄)₃ are three-fold coordinated and are located near the bottle-neck in the path between M1 and M2 sites of the Nasicon structure.     

Synthesis, structure, and properties of [Be(H2O)4][UO2(CH3COO)3]2

Crystals of previously unknown compound [Be(H₂O)₄][UO₂(CH₃COO)₃]₂ were prepared and studied by X-ray diffraction analysis. The compound crystallizes in the tetragonal system, unit cell parameters (at 100 K): a = 10.3647(3), c = 23.4127(8) Å, V = 2515.16(13) ų, space group I4₁/a, Z = 4, R = 0.0194. The structure consists of mononuclear complexes [Be(H₂O)₄]²⁺ and [UO₂(CH₃COO)₃]^? linked with each other by electrostatic interactions and hydrogen bonds formed by water molecules and O atoms of acetate anions. The compound was also studied by methods of thermal analysis and IR spectroscopy.     

纳米微孔杂多化合物Na[Fe2(O2H3)Mo2O8](Ⅰ)和(NH4)[Fe(MoO4)2](Ⅱ)的结构特征

通过采用水热合成法得到了二种具有纳米筛孔的氧簇化合物Na[Fe2(O2H3)Mo2O8](Ⅰ)和(NH4)[Fe(Mo O4)2](Ⅱ).晶体(Ⅰ)属于单斜晶系,空间群为C2/m,晶胞参数为:a=9.5450(17),b=6.4381(9),c=0.76405(12)nm;β=116.128(4),Z=2,R1=0.0219,Rw=0.0756.晶体(Ⅱ)属于正交晶系,空间群为Pnma,晶胞参数为:a=1.4782(3),b=0.56774(11),c=0.87653(18)nm;Z=4,R1=0.0212,Rw=0.0513.     

Crystal Structure of U(VI) Peroxo Complex with Triphenylphosphine Oxide {(UO2)2O2[OP(C6H5)3]6}(ClO4)2

The peroxo complex {(UO₂)₂O₂[OP(C₆H₅)₃]₆}(ClO₄)₂ was synthesized, and its crystal structure was determined [triclinic unit cell: a = 10.523(2), b = 16.242(3), c = 16.978(3) Å, = 65.79(3)°, = 85.06(3)°, = 77.14(3)°, space group P-1, Z = 1, V = 2580.1(9) ų, d _{c a l c} = 2.789 g cm^{- 3}; CAD4, MoK , graphite monochromator, direct method, R ₁ = 0.0368 for 3115 observed reflections, wR ₂ = 0.1107 for 4403 unique reflections, 622 refined parameters]. {(UO₂)₂O₂[OP(C₆H₅)₃]₆}(ClO₄)₂ has monomeric structure and consists of the complex cations {(UO₂)₂O₂[OP(C₆H₅)₃]₆}^{2 +} and ClO₄ ^- anions. The uranium atom has a pentagonal-bipyramidal oxygen surrounding (CN 7). Uranyl groups UO₂ ^{2 +} are linear and symmetrical, the U = O bond lengths are 1.780(8) and 1.787(8) Å, the O(1) = U = O(2) bond angles are 178.7(4) Å. The equatorial planes of bipyramids are formed by oxygen atoms of three TPPO molecules [U-O_{T P P O} 2.352(8)-2.368(7) Å, average 2.362 Å] and peroxo group O₂ ^{2 -} [U-O_{p e r} 2.285(8) and 2.323(8) Å, average 2.305 Å]. Two pentagonal bipyramids sharing the common edge O(3)-O(3)^(a) form the centrosymmetrical peroxo-bridged diuranyl complex {(UO₂)₂O₂[OP(C₆H₅)₃]₆}^{2 +} with the [UO₂O₂UO₂]^{2 +} core. The length of the O(3)-O(3)^{( 9a )} edge is 1.426(15) Å.     

Synthesis and Crystal Structure of Cs4[UO2(CO3)3]

Light green transparent crystals of Cs₄[UO₂(CO₃)₃] were prepared by evaporation from aqueous solutions. The crystal structure was refined to R ₁ = 0.039 (wR ₂ = 0.081) for 2311 reflections with |Fhkl| 4|Fhkl|. Monoclinic system, space group C2/c, a = 11.5131(9), b = 9.6037(8), c = 12.9177(10) Å, = 93.767(2)°, V = 1425.2(2) ų. The structure of Cs4[UO2(CO3)3] consists of isolated complex ions [UO₂(CO₃)₃]^{4 -} formed by uranyl cation UO₂ ^{2 +} and three CO₃ ^{2 -} groups. The equatorial planes of the [UO₂(CO₃)₃]^{4 -} ions are approximately parallel to the (201) plane. The nine-coordinate Cs⁺ cations are located between the complex anions. The compound is isostructural with M4[UO2(CO3)3] with M = K, NH₄, and Tl, but not isostructural with Na₄[UO₂(CO₃)₃].     

Tetramethylammonium Neptunium(IV) Isothiocyanate [N(CH3)4]4[Np(NCS)8]

A new Np(IV) complex, [N(CH₃)₄]₄[Np(NCS)₈], was prepared. Its crystal structure was determined, and the absorption spectra in the IR and near IR ranges were measured. Crystal data: a = 27.280(6), b = 12.288(3), c = 13.493(3) Å, space group Pna2₁, Z = 4, V = 4523(2) A³, R = 0.044, wR(F ²) = 0.091. The crystal structure of the compound consists of [Np(NCS)₈]^{4 -} anions and N(CH₃)₄ ⁺ cations. The coordination polyhedron of the Np atom is a distorted tetragonal antiprism formed by the nitrogen atoms of eight NCS^- ions.     

[Mn(en)3]2·Sn2Se4Te2的结构和光吸收性能

按照K2Se:K2Te2:MnCl2@4H2O:SnCl2 2H2O:Se:乙二胺(en)＝3.8:1:2:2:6:270的摩尔比配料,采用溶剂热法使原料混合物在180℃反应7 d,得到黑色块状晶体[Mn(en)3]2@Sn2Se4Te2.属于三斜晶系,空间群为P-1,晶胞参数a＝0.91428(7)nm,b＝1.02781(7)nm,c＝1.15745(8)nm,α＝94.632(2)°,β＝100.944(2)°,γ＝115.918(1)°,V＝0.94382(12)nm3,Z＝1.晶体由[Mn(en)3]2+和(Sn2Se4Te2)4-堆积而成.具有Zintl结构的特征半导体[Mn(en)3]2@Sn2Se4Te2的光学能隙(Eg)为2.2 eV.当温度低于190℃时,[Mn(en)3]2@Sn2Se4Te2晶体是稳定的.详细讨论了这类化合物的组成对晶体结构和光吸收性能的影响.     

Synthesis and crystal structure of a uranyl bichromate, [CH6N3]2[(UO2)(CrO4)(Cr2O7)](H2O)

Crystals of the first uranyl bichromate, [CH₆N₃]₂[(UO₂)(CrO₄)(Cr₂O₇)](H₂O), were obtained by evaporation from aqueous solutions. The compound crystallizes in the triclinic system, space group $P\bar 1$ , a = 7.1829(17), b = 9.304(3), c = 14.884(4) Å, α = 102.43(2)°, β = 97.98(2)°, γ = 101.07(2)°, V = 936.3(5) ų, Z = 2. The structure was solved by direct methods and refined by the full-matrix least-squares method to R ₁ = 0.064 (wR ₂ = 0.138) for 2225 reflections with |F _hkl | ≥ 4σ(|F _hkl |). The structure is based on infinite [(UO₂)(CrO₄)(Cr₂O₇)]^2? chains where [UO₇]^8? pentagonal bipyramids are linked by tridentate [Cr(1)O₄]^2? groups and [Cr₂O₇]^2? groups; these chains run along x axis and are oriented parallel to $(0\bar 11)$ . Trigonal [CH₆N₃]⁺ cations and water molecules are arranged between the chains.     

A promising birefringent crystal Ba2Na3(B3O6)2F

Bulk crystals of Ba₂Na₃(B₃O₆)₂F (BNBF) have been successfully grown by top-seeded solution growth (TSSG) technique. Its transmittance spectra show a wide transparency range from 186 nm to 3000 nm. The refractive indices in 13 wavelengths were measured with high accuracy and the Sellmeier equations were obtained, which demonstrated that the title crystal displayed a birefringence (Δn = 0.1030 at 588 nm) comparable to that of the commercial birefringent crystal α-BBO (the high temperature form of BaB₂O₄). A prototype Glan-Taylor polarizer made of BNBF prisms was fabricated, which showed high transparency and large optical extinction ratio similar to the commercial polarizer made of α-BBO. In addition, BNBF crystal is less moisture sensitive than that of α-BBO, thus BNBF can be a potential new birefringent crystal.     

Synthesis and crystal structure of a new uranyl selenite(IV)-selenate(VI), [C5H14N]4[(UO2)3(SeO4)4(HSeO3)(H2O)](H2SeO3)(HSeO4)

Crystals of a new uranyl selenite(IV)-selenate(VI), [C₅H₁₄N]₄[(UO₂)₃(SeO₄)₄(HSeO₃)(H₂O)]·(H₂SeO₃)(HSeO₄) were obtained by evaporation from aqueous solutions. The compound crystallizes in the triclinic system, space group $P\bar 1$ , a = 11.7068(9), b = 14.8165(12), c = 16.9766(15) Å, α = 73.899(6)°, β = 76.221(7)°, γ = 89.361(6)°, V = 2743.0(4) ų, Z = 2. The crystal structure was solved by direct methods and refined to R ₁ = 0.081 (wR ₂ = 0.150) for 6966 reflections with |F _hkl | ≥ 4σ(|F _hkl |). The structure is based on [(UO₂)₃(SeO₄)₄(HSeO₃)(H₂O)]^3? layers formed by joining uranyl pentagonal bipyramids, selenate tetrahedra, and selenite pyramids. The [HSe(VI)O₄]^? anions, [H₂Se(IV)O₃] molecules, and protonated methylbutylamine cations are arranged between the layers.     

Studies on three-dimensional coordination polymer [Cd2(N2H4)2(N3)4]n: crystal structure, thermal decomposition mechanism and explosive properties

A 3D coordination polymer of cadmium(II) hydrazine azide, [Cd2(N2H4)2(N3)4]n, was synthesized and characterized by elemental analysis and Fourier transform infrared (FT-IR) spectrum. Its crystal structure was determined by single crystal X-ray diffraction analysis. The crystal belongs to monoclinic, P2(1)/c space group, a=12.555(2)A, b=11.724(2)A, c=7.842(1)A, beta=94.56(2) degrees and Z=4. The crystal contains two crystallographically independent sets of distorted octahedral Cd(II) atoms and dimeric units of Cd2N2, Cd2(NNN)2, Cd2(NN)2 through double micro-1, 1 azide bridges, micro-1, 3 azide bridges and bidentate bridging hydrazine ligands, respectively, and thus generating a 3D network structure. The thermal decomposition mechanism of the complex was studied by using differential scanning calorimetry (DSC), thermogravimetry-derivative thermogravimetry (TG-DTG) and FT-IR techniques. Under nitrogen atmosphere with a heating rate of 10 degrees C/min, the thermal decomposition of the complex contained two intense exothermic decomposition processes in the range of 150-304 degrees C in the DSC curve, and the final decomposed residue at 500 degrees C was Cd. Sensitivity tests revealed that the title complex is very insensitive to external stimuli.     

Phase diagrams of the ternary liquid systems [Ce(NO3)3(TBP)3]-C10H22-[UO2(NO3)2(TBP)2] and [Ce(NO3)3(TBP)3]-C10H22-[Th(NO3)4(TBP)2] and of the quaternary liquid system [Ce(NO3)3(TBP)3]-C10H22-[UO2(NO3)2(TBP)2]-[Th(NO3)4(TBP)2]

The phase diagrams of the ternary liquid systems [Ce(NO₃)₃(TBP)₃]-C₁₀H₂₂-[UO₂(NO₃)₂(TBP)₂] and [Ce(NO₃)₃(TBP)₃]-C₁₀H₂₂-[Th(NO₃)₄(TBP)₂] and of the quaternary liquid system [Ce(NO₃)₃(TBP)₃]-C₁₀H₂₂-[UO₂(NO₃)₂(TBP)₂]-[Th(NO₃)₄(TBP)₂] at T = 298.15 K are constructed. The phase diagrams are characterized by areas of homogeneous solutions and of two-phase liquid systems (systems with phase separation), with one phase (I) enriched in [Ce(NO₃)₃(TBP)₃], [Th(NO₃)₄(TBP)₂], and [UO₂(NO₃)₂(TBP)₂], and the other phase (II), in C₁₀H₂₂. Using the data on the mutual solubility of the components in the systems under consideration and equations of the NRTL model, the parameters of intermolecular interactions and the excess Gibbs energies (G ^ex) were calculated for the binary, ternary, and quaternary systems. Passing from the ternary system [Ce(NO₃)₃(TBP)₃]-C₁₀H₂₂-[Th(NO₃)₄(TBP)₂] to the quaternary system [Ce(NO₃)₃(TBP)₃]-C₁₀H₂₂-[UO₂(NO₃)₂ (TBP)₂]-[Th(NO₃)₄(TBP)₂] does not appreciably affect the distribution of C₁₀H₂₂ between phases I and II, but leads to the redistribution of [Ce(NO₃)₃(TBP)₃] into phase II and of [Th(NO₃)₄(TBP)₂] into phase I.     

Synthesis,Structure, and Physicochemical Properties of AI 4[UO2(CO3)3]·nH2O (AI = Li,Na, K,NH4)

Procedures for the synthesis of Li₄[UO₂(CO₃)₃]·1.5H₂O, Na₄[UO₂(CO₃)₃], K₄[UO₂(CO₃)₃], (NH₄)₄[UO₂(CO₃)₃], and K₃Na[UO₂(CO₃)₃] were optimized. The structures of these compounds and their thermolysis were studied by X-ray diffraction, precision IR spectroscopy, and thermal analysis. The standard enthalpies of formation of these compounds at 298.15 K were determined by reaction calorimetry.     

[Cu(1,4-C4H12N2)2(ClO4)2]n(H2O)2n,a novel butane-1,4-diamine-bridged two-dimensional copper(II) square network: Synthesis,structure, and magnetic properties

A novel butane-1,4-diamine-bridged copper(II) compound was synthesized via solvent diffusion route with high yield. Each copper is coordinated by four butane-1,4-diamine ligands, each of which in turn links with two copper atoms to form a two-dimensional (2D) square network. Interestingly, the title compound features a cross-linking rhombic channel (ca. 5.06 × 14.73 Å) parallel to the crystallographic b axis. And magnetic result measured indicates the presence of localized unpaired electrons in the structure and thus the cupric Cu(II) state.