Synthesis,crystal structure,and catalytic performance of two 3-D supramolecular compounds: (C7N2H7)3(C7N2H6) · PMo12O40 · 2H2O and (C7N2H7)3(C7N2H6)2 · AsMo12O40 · 3H2O

Two organic–inorganic compounds based on Keggin building blocks have been synthesized by hydrothermal methods, (C₇N₂H₇)₃(C₇N₂H₆)?·?PMo₁₂O_40?·?2H₂O (1) and (C₇N₂H₇)₃(C₇N₂H₆)_2?·?AsMo₁₂O_40?·?3H₂O (2) (C₇N₂H₆?=?benzimidazole). Single-crystal X-ray analysis revealed that 1 crystallized in the triclinic system, P-1 space group with a?=?9.8980(4)?Å, b?=?11.2893(4)?Å, c?=?25.8933(9)?Å, α?=?93.307(2)°, β?=?90.630(2)°, γ?=?108.330(2)°, V?=?2740.68(18)?ų, Z?=?2, R ₁(F)?=?0.0740, ωR ₂(F ²)?=?0.1511, and S?=?1.037; 2 crystallized in the triclinic system, P-1 space group with a?=?12.3353(4)?Å, b?=?13.2649(4)?Å, c?=?20.2878(6)?Å, α?=?95.6630(10)°, β?=?100.1720(10)°, γ?=?99.3940(10)°, V?=?3195.72(17)?ų, Z?=?2, R ₁(F)?= 0.0329, ωR₂ (F ²)?=?0.1236, and S?=?1.088. The two compounds show a layer framework constructed from Keggin-polyoxoanion clusters and benzimidazole via hydrogen bonds and π–π stacking interactions, resulting in a 3-D supramolecular network. Both have high catalytic activity for oxidation of methanol. When the initial concentration of the methanol is 5.37?g?m^?3 in air and the flow velocity is 4.51?mL?min^?1, methanol is completely eliminated at 150°C for 1 (160°C for 2).     

Cupro(I)-π-complexes with 1-allyloxybenzotriazole: Synthesis and crystal structure of CuBF4 · 2C6H4N3(OC3H5) · H2O and CuCF3COO · C6H4N3(OC3H5)

The crystals of copper(I) π-complexes CuBF₄ · 2C₆H₄N₃(OC₃H₅) · H₂O (I) and CuCF₃COO · C₆H₄N₃(OC₃H₅) (II) were obtained by alternating-current electrosynthesis and studied by X-ray diffraction: I, space group P2₁/n, a = 10.226(8), b = 13.233(10), c = 16.30(1) Å, β = 98.13(1)°, V = 2249(2) ų, Z = 4, R = 0.0705, 577 reflections; I, space group P $ P\bar 1 The crystals of copper(I) π-complexes CuBF₄ · 2C₆H₄N₃(OC₃H₅) · H₂O (I) and CuCF₃COO · C₆H₄N₃(OC₃H₅) (II) were obtained by alternating-current electrosynthesis and studied by X-ray diffraction: I, space group P2₁/n, a = 10.226(8), b = 13.233(10), c = 16.30(1) ?, β = 98.13(1)°, V = 2249(2) ?³, Z = 4, R = 0.0705, 577 reflections; I, space group P , a = 8.8625(7), b = 9.0647(4), c = 9.1650(5) ?, α = 68.37(2)°, β = 85.31(3)°, γ = 69.86(2)°, V = 646(4) ?³, Z = 2, R = 0.1354, 2669 reflections. In compound I, the tetrahedrally distorted trigonal pyramidal environment of the copper atom comprises two nitrogen atoms of two organic molecules (L), the C=C bond of another L molecule, and the O atom of the water molecule. Due to the bridging function of L molecule, infinite chains [Cu · 2C₆H₄N₃(OC₃H₅) · H₂O] _n are formed in the structure along the y axis. The chains are, in turn, assembled into layers through strong O-H…F hydrogen bonds involving both hydrogen atoms of the water molecule and fluorine atoms of the BF₄⁻ anion. In compound II, two bridging oxygen atoms of two trifluoroacetate anions and two copper atoms form a centrosymmetric dimer. The nitrogen atom of the benzotriazole ring of one molecule L and the C=C double bond of the allyl group of the other molecule L complete the distorted coordination tetrahedron of the metal atom. Owing to the bridging function of the L molecule, the [CuCF₃COO · C₆H₄N₃(OC₃H₅)]₂ dimers are connected to form infinite double chains associated in a three-dimensional framework by only weak interactions. The replacement of the covalently bonded trifluoroacetate anion by an outer-sphere tetrafluoroborate ion opens up the possibility for metal atom binding to three L molecules simultaneously. Original Russian Text ? E.A. Goreshnik, M.G. Mys’kiv, 2008, published in Koordinatsionnaya Khimiya, 2008, Vol. 34, No. 11, pp. 826–830.     

C3N6H6(H3BO3)2的合成及晶体结构

以三聚氰胺和硼酸为原料在水溶液中反应合成出了一种新的BCN化合物先驱体C3N6H6(H3BO3)2。XRD表征结果表明三聚氰胺和硼酸的最佳配比为1∶3(物质的量比)。用单晶X-射线衍射分析法测定了该化合物的晶体结构。该化合物属单斜晶系,空间群为P21/C,晶胞参数为a=0.3597(7)nm,b=2.0105(4)nm,c=1.4112(3)nm,α=90,°β=92.07(3),°γ=90,°V=1.0199(3)nm3,Z=4,D c=1.627g.cm-3,μ(MoKα)=0.144mm-1,F(000)=520。晶体结构经全矩阵最小二乘法修正,最终可靠因子R1=0.0519,wR2=0.1361。该化合物是由C3N6H6分子和H3BO3分子通过氢键加合组装形成的三维超分子结构化合物。     

An infrared and Raman spectroscopic study of Td-type 4,4′-bipyridylcadmium(II) tetracyanometallate (II) benzene (1/2) clathrates: Cd(C10H8N2)Cd(CN)4 · 2C6H6 and Cd(C10H8N2)Hg(CN)4 · 2C6H6

Two new benzene clathrates of the form Cd(4,4-bipyridyl)M(CN)₄ · 2C₆H₆, (M=Cd or Hg) have been prepared in powder form. Their spectral data were compared with those of the corresponding host complexes and found to be consistent with the host structure found in Td-type clathrates.     

Expansion of antimonato polyoxovanadates with transition metal complexes: (Co(N3C5H15)2)2[{Co(N3C5H15)2}V15Sb6O42(H2O)]·5H2O and (Ni(N3C5H15)2)2[{Ni(N3C5H15)2}V15Sb6O42(H2O)]·8H2O

Two new polyoxovanadates (Co(N(3)C(5)H(15))(2))(2)[{Co(N(3)C(5)H(15))(2)}V(15)Sb(6)O(42)(H(2)O)]·5H(2)O (1) and (Ni(N(3)C(5)H(15))(2))(2)[{Ni(N(3)C(5)H(15))(2)}V(15)Sb(6)O(42)(H(2)O)]·8H(2)O (2) (N(3)C(5)H(15) = N-(2-aminoethyl)-1,3-propanediamine) were synthesized under solvothermal conditions and structurally characterized. In both structures the [V(15)Sb(6)O(42)(H(2)O)](6-) shell displays the main structural motif, which is strongly related to the {V(18)O(42)} archetype cluster. Both compounds crystallize in the triclinic space group P1 with a = 14.3438(4), b = 16.6471(6), c = 18.9186(6) ?, α = 87.291(3)°, β = 83.340(3)°, γ = 78.890(3)°, and V = 4401.4(2) ?(3) (1) and a = 14.5697(13), b = 15.8523(16), c = 20.2411(18) ?, α = 86.702(11)°, β = 84.957(11)°, γ = 76.941(11)°, and V = 4533.0(7) ?(3) (2). In the structure of 1 the [V(15)Sb(6)O(42)(H(2)O)](6-) cluster anion is bound to a [Co(N(3)C(5)H(15))(2)](2+) complex via a terminal oxygen atom. In the Co(2+)-centered complex, one of the amine ligands coordinates in tridentate mode and the second one in bidentate mode to form a strongly distorted CoN(5)O octahedron. Similarly, in compound 2 an analogous NiN(5)O complex is joined to the [V(15)Sb(6)O(42)(H(2)O)](6-) anion via the same attachment mode. A remarkable difference between the two compounds is the orientation of the noncoordinated propylamine group leading to intermolecular Sb···O contacts in 1 and to Sb···N interactions in 2. In the solid-state lattices of 1 and 2, two additional [M(N(3)C(5)H(15))(2)](2+) complexes act as countercations and are located between the [{M(N(3)C(5)H(15))(2)}V(15)Sb(6)O(42)(H(2)O)](4-) anions. Between the anions and cations strong N-H···O hydrogen bonds are observed. In both compounds the clusters are stacked along the b axis in an ABAB fashion with cations and water molecules occupying the space between the clusters. Magnetic characterization demonstrates that the Ni(2+) and Co(2+) cations do not significantly couple with the S = 1/2 vanadyl groups. The susceptibility data can be successfully reproduced assuming a distorted ligand field for the Co(2+) ions (1) and an O(h)-symmetric Ni(2+) ligand field (2).     

[Mn3O(O2CC6H5)6(C3H4N2)3]·C6H5CO2·0.5H2O的 合成、晶体结构及磁性质

Mn(O2CMe)2·4H2O、咪唑、苯甲酸和N(n-Bu)4MnO4在无水乙醇溶剂中反应,制备得到锰的三核μ3-O桥联配位化合物[Mn3O(O2CC6H5)6(C3H4N2)3]·C6H5CO2·0.5H2O.该配位化合物的X射线单晶衍射表明,其属于单斜晶系,空间群P21/C,晶胞参数：a=1.52832(19)nm,b=1.9722(2)nm,c=2.1023(3)nm,β=92.597(3)°,Z=4.变温磁化率(5～280K)研究表明,该配位化合物中3个锰离子在低温下存在弱的反铁磁性耦合,交换积分J=-2.34cm^-1。     

Syntheses and Crystal Structures of (H3O)(C3H5N2)[Mn(OH)6 Mo6O18]·3.5H2O and (H3O)3[Co(OH)6Mo6O18]·7H2O

The crystals of the title compounds (H3O)(C3H5N2)[Mn(OH)6Mo6O18]·3.5H2O 1 and (H3O)3[Co(OH)6Mo6O18]·7H2O 2 have been prepared and structurally determined by X-ray single-crystal diffraction. Compound 1 crystallizes in monoclinic, space group C2/c with a = 21.5018(9), b = 10.9331(5), c = 11.8667(5)A,β = 95.3570(10)o, V = 2777.5(2)A3, Z = 4, Dc = 2.802 g/cm3, Mr = 1171.80,μ(MoKα) = 3.173 mm-1, F(000) = 223, the final R = 0.0458 and wR = 0.1041 for 2093 observed reflections (I>2σ(I)); Compound 2 crystallizes in monoclinic, space group P21/c with a = 11.4042(12), b = 10.9481(11), c = 11.6722(12)A, β= 99.948(2)o, V = 1435.4(3)A3, Z = 2, Dc = 2.794 g/cm3, Mr = 1207.80,μ(MoKα) = 3.223 mm-1, F(000) = 1160, the final R = 0.0544 and wR = 0.1066 for 1906 observed reflections (I > 2σ(I)). Both compounds 1 and 2 adopt the Anderson structure, in which the anion is of centrosymmetry and formed by six octahedral edge-sharing MoO6 units surrounding the central MO6 (M = Mn or Co) octahedron.     

Why are [P(C6H5)4](+)N3- and [As(C6H5)4](+)N3- ionic salts and Sb(C6H5)4N3 and Bi(C6H5)4N3 covalent solids? A theoretical study provides an unexpected answer

A recent crystallographic study has shown that, in the solid state, P(C(6)H(5))(4)N(3) and As(C(6)H(5))(4)N(3) have ionic [M(C(6)H(5))(4)](+)N(3)(-)-type structures, whereas Sb(C(6)H(5))(4)N(3) exists as a pentacoordinated covalent solid. Using the results from density functional theory, lattice energy (VBT) calculations, sublimation energy estimates, and Born-Fajans-Haber cycles, it is shown that the maximum coordination numbers of the central atom M, the lattice energies of the ionic solids, and the sublimation energies of the covalent solids have no or little influence on the nature of the solids. Unexpectedly, the main factor determining whether the covalent or ionic structures are energetically favored is the first ionization potential of [M(C(6)H(5))(4)]. The calculations show that at ambient temperature the ionic structure is favored for P(C(6)H(5))(4)N(3) and the covalent structures are favored for Sb(C(6)H(5))(4)N(3) and Bi(C(6)H(5))(4)N(3), while As(C(6)H(5))(4)N(3) presents a borderline case.     

Synthesis and Crystal Structure of (C6N3H18)2Ti4O4(C2O4)7·4H2O

The title compound (C6N3H18)2Ti4O4(C2O4)7(4H2O 1 (C13H22N3O18Ti2, Mr = 604.14) was synthesized by the reaction of Ti(SO4)2, H2C2O4(2H2O and N-(2-ammonioethyl)- piperazinium (AEPP) in aqueous solution. The single-crystal X-ray analysis has revealed that 1 crystallizes in the triclinic system, space group Pī with a = 9.1437(6), b = 11.4991(10), c = 11.6975(8)A, α = 96.2915(18), β = 107.998(3), γ = 104.276(4)°, V = 1110.35(14)A3, Z = 2, Dc = 1.807 g/cm3, F(000) = 618, μ = 0.815 mm－1, the final R = 0.0463 and wR = 0.1264 for 3718 observed reflections with I > 2σ(I). X-ray crystal-structure analysis suggests that compound 1 consists of [Ti4O4(C2O4)7]6－ anion and two protonated N-(2-ammonioethyl)piperazinium cations. The anions are linked into an infinite chain through Ti4O4(C2O4)8 by sharing the oxalates as bridging ligands.     

Syntheses and structures of two new M6Li8(N3)a6 cluster-unit based compounds: Cs4Re6S8(N3)6·H2O and Na2Mo6Br8(N3)6·2H2O

The two new cluster compounds, Cs₄Re₆S₈(N₃)₆·H₂O (1) and Na₂Mo₆Br₈(N₃)₆·2H₂O (2), have been prepared via solution chemistry route, starting from the Cs₄Re₆S₈Br₆CsBr and Mo₆Br₁₂ precursors synthesized by solid state chemistry techniques, and structurally characterized (crystal data: Cs₄Re₆S₈(N₃)₆·H₂O (1): Orthorhombic, space group Pnam, a=10.0651(1) Å, b=15.8856(2) Å, c=20.1714(3) Å, V=3225.2(7) Å³, Z=4, d_calc=4.48 g cm⁻³, μ=27.43 mm⁻¹; Na₂Mo₆Br₈(N₃)₆·2H₂O (2): Orthorhombic, space group Ibam, a=11.5643(3) Å, b=14.3959(5) Å, c=17.0340(7) Å, V=2835.8(2) ų, Z=4, d_calc=3.63 g cm⁻³, μ=13.91 mm⁻¹). Their structures revealed that in both cases, the M₆Lⁱ₈ cluster core remains unchanged in the starting and final compounds whereas the bromine apical ligands (Br^a) are substituted by N₃ azide groups leading to M₆Lⁱ₈(N₃)^a₆ cluster unit. The new Cs₄Re₆S₈(N₃)₆·H₂O is the first example of a compound containing an octahedral rhenium cluster coordinated to azide groups.     

Rb[C6H3(COOH)2(COO–)] · [C6H3(COOH)3] · 2H2O: Synthesis,Crystal Structure,and Properties

The salt Rb[C₆H₃(COO)₂(^–)] · [C₆H₃(COOH)₃] · 2H₂O (I) of trimesic acid was synthesized and its thermal stability and conductivity (10^–11 ohm^–1 cm^–1 at 298 K) were measured. Molecular and crystal structures of I were established by X-ray diffraction analysis. Hydrogen bonding system in complex I was detected by IR and Raman spectroscopies. X-ray diffraction data agree with vibration spectroscopy data.     

Crystal structure of copper(I) chloride π-complexes with diallylamine: (C6H12N)2Cu7Cl9·H2O and 2CuCl·C6H11N

For the first time we have synthesized and studied by X-ray structural analysis two novel copper(I) chloride -complexes with diallylamine (DAA): [H(DAA)]₂Cu₇Cl₉·H₂O (D) and 2CuCl·DAA (E). Compound D is isostructural to the complex [H(DAA)]₂Cu₇Br₉·H₂O studied earlier: space group Pnam, a=15.934(8), b=14.817(6), c=11.368(6) , V=2684(4) ³, and Z=4 for [(C₆H₁₂N)₂ Cu₇Cl₉·H₂O]. Crystals E are triclinic: space group P1, a=7.373(2), b=9.743(4), c=11.351(8) , =84.05(4), =101.26(4), =103.31(3)°, V=914(2) ³, and Z=2 for [Cu₄Cl₄·(C₆H₁₁N)₂]. The layers of the structure are formed by combining the armchair-shaped cycles Cu₄Cl₄ via the tridentate DAA molecules.I. Franko Lvov State University, Ukrainian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 34, No. 6, pp. 43–48, November–December, 1993.Translated by T. Yudanova     

Two binuclear complexes containing the enrofloxacinate anion: Cd2(C19H21N3O3F)4(H2O)2 · 4H2O and Pb2(C19H21N3O3F)4 · 4H2O

The syntheses and crystal structures of the closely related but non-isostructural Cd₂(C₁₉H₂₁N₃O₃F)₄(H₂O)₂?·?4H₂O (1) and Pb₂(C₁₉H₂₁N₃O₃F)₄?·?4H₂O (2) are described, where C₁₉H₂₁N₃O₃F^? is enrofloxacinate (enro). Both compounds contain centrosymmetric, binuclear, neutral complexes incorporating a central diamond-shaped M₂O₂ (M?=?Cd, Pb) structural unit. The Cd²⁺ coordination polyhedron in 1 is a CdO₆ trigonal prism, including one coordinated water. The Pb²⁺ coordination polyhedron in 2 can be described as a very distorted square-based PbO₅ pyramid, although two additional short Pb?···?O (<3.1?Å) contacts are also present. In the crystal of the cadmium complex, O–H?···?O hydrogen bonds lead to a layered structure. In the lead compound, O–H?···?O and O–H?···?N interactions lead to chains in the crystal. Crystal data: 1: C₇₆H₉₆Cd₂F₄N₁₂O₁₈, M _r?=?1766.45, triclinic, P 1, a?=?12.185(2)?Å, b?=?12.306(3)?Å, c?=?14.826(3)?Å, α?=?68.15(3)°, β?=?70.28(3)°, γ?=?86.11(3)°, V?=?1938.2(7)?ų, Z?=?1, T?=?298 K, R(F)?=?0.030, wR(F ²)?=?0.079. 2: C₇₆H₈₈F₄N₁₂O₁₆Pb₂, M _r?=?1920.00, triclinic, P 1, a?=?12.0283(4)?Å, b?=?12.7465(4)?Å, c?=?13.0585(4)?Å, α?=?83.751(1)°, β?=?74.635(1)°, γ?=?81.502(1)°, V?=?1904.3(1)?ų, Z?=?1, T?=?298?K, R(F)?=?0.021, wR(F ²)?=?0.049.     

[Cu(C8H4F3O2S)2(C12H8N2)]·C3H6O的合成及其晶体结构

标题配合物 [Cu(C8H4 F3O2 S) 2 (C12 H8N2 ) ]·C3H6 O属于三斜晶系 ,空间群为P1,并测得如下晶胞参数a =10 .5 77(3) ,b =15 .72 2 (4) ,c =10 .133(2 ) ,α =94 .5 3(2 ) ,β =10 0 .81(2 ) ,γ =96 .18(2 )° ,V =16 37.0 3 3,Z =2 ,Mr =74 4.18,Dx =1.5 1× 10 6 g·m- 3,F(0 0 0 ) =5 2 6 ,μ =8 2 4cm- 1,最终偏差因子为R =0 .0 83,Rw=0 .0 74。Cu(II)与 2个 4 ,4 ,4 三氟 1 (2 噻吩基 )丁二酮 1,3中的四个氧原子和菲咯啉中的两个氮原子 ,组成了一个畸变的八面体构型。     

Synthesis and structure of a three-dimensional lanthanide complex [Tm2(C5H3N(COO)2)3(H2O)3)]·H2O

A new three-dimensional complex [Tm₂(C₅H₃N(COO)₂)₃(H₂O)₃)]·H₂O (PDC?=?3,5-pyridinedicarboxylate), has been synthesized and its structure determined by x-ray single crystal diffraction methods. Complex 1 crystallizes in the monoclinic space group P2(1)/n with a?=?14.579(4), b?=?11.193(3), c?=?14.839(5)?Å, β?=?94.009(6)°, U?=?2415.5(13)?ų. Two independent PDC ligands bridge Tm^III ions from different orientations to form a network. Thermogravimetric analyses on compound 1 show its high structural stability to 410°C.     

Tetranuclear bismuth complexes Bi4(O)2(O2CC6H2F3-3,4,5)8 · 2C6H6 and Bi4(O)2(O2CC6H2F3-3,4,5)8 · 2C6H4Me2-1,4: Synthesis and structures

X-ray diffraction study of tetranuclear organobismuth complexes Bi₄(O)₂(O₂CC₆H₂F₃-3,4,5)₈ · 2⁶-C₆H₆ and Bi₄(O)₂(O₂CC₆H₂F₃-3,4,5)₈ · 2(C₆H₄Me₂-1,4) revealed four Bi atoms connected through the bridging carboxylate ligands and the O atoms. The coordination sphere of the terminal Bi atoms includes the chelate carboxylate ligand and the 6-arene molecule. The bridging O atoms are tricoordinated, the distances between the terminal Bi atom and the center of benzene molecule (1,4-dimethylbenzene) are 3.024 Å(3.131 Å).Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 1, 2005, pp. 4–11.Original Russian Text Copyright © 2005 by Sharutin, Egorova, Sharutina, Ivanenko, Adonin, Starichenko, Pushilin, Gerasimenko.     

Hydrothermal synthesis and characterization of a new organically templated three-dimensional open-framework gallium phosphate–phosphite (C6N2H18)2(C6N2H17)Ga15(OH)8(PO4)2(HPO4)12(HPO3)6·2H2O

Using H₃PO₃ as a phosphorus source and oxalic acid as a reducing agent, the first three-dimensional open-framework gallium phosphate–phosphite formula as (C₆N₂H₁₈)₂(C₆N₂H₁₇)Ga₁₅(OH)₈(PO₄)₂(HPO₄)₁₂(HPO₃)₆·2H₂O (1), has been hydrothermally synthesized in the presence of N,N,N′,N′-tetramethylenediamine (TMEDA) as a structure-directing agent. Compound 1 crystallizes in trigonal system with space group P ? 3, a = b = 19.046(3) Å, c = 8.3306(17) Å, γ = 120°, V = 2617.1(7) Å³, and Z = 1. Its 3-D network is based on alternated Ga-centered (GaO₄ tetrahedra, GaO₅ trigonal bipyramids, and GaO₆ octahedra) and P-centered (PO₄^3?, HPO₄^2?, and HPO₃^2?) units. Protonated organic amines and water molecules are located in the 12-membered ring channels.     

Fourier-transform Raman and infrared spectra and normal coordinate analysis of (C6H5)2BiCl and [N(CH3)4]+[(C6H5)2BiCl2]−

The vibrational properties of the diphenylbismuth(III) chloride compounds (C₆H₅)₂BiCl and [N(CH₃)₄]⁺[(C₆H₅)₂BiCl₂]⁻ have been investigated. A comprehensive assignment of the fundamental modes in the measured Fourier-transform Raman and infrared spectra has been carried out. Normal coordinate calculations of these compounds based on new X-ray crystal structure data have been performed to identify the BiCl stretching and bending vibrations of both compounds. For [N(CH₃)₄]⁺[(C₆H₅)₂BiCl₂]⁻ in the solid state, the ν_s(BiCl₂) and ν_as(BiCl₂) occur at 215 cm⁻ (Raman) and 237 cm⁻ (Raman), respectively, in good agreement with the calculated wavenumbers. The force constant calculation yields a BiCl stretching force constant of 0.89 × 10² N m⁻¹.     

Coordination behavior of 1,4-diallylpiperazinium and 1-allyloxybenzotriazole toward silver(I) in the crystalline π-complexes [Ag2(C4H8N2(C3H5)2(H+)2)(H2O)2(NO3)2](NO3)2 and [Ag(C6H4N3(OC3H5)(NO3))]

Reactions of a solution of AgNO₃ in aqueous methanol with solutions of 1,4-diallylpiperazine (acidified with HNO₃ to pH = 4) and 1-allyloxybenzotriazole in ethanol gave the crystalline silver(I) π-complexes [Ag₂(C₄H₈N₂(C₃H₅)₂(H⁺)₂)(H₂O)₂(NO₃)₂](NO₃)₂ (I) and [Ag(C₆H₄N₃(OC₃H₅)(NO₃))] (II). Their crystal structures were determined by X-ray diffraction. Crystals of complexes I and II are monoclinic, space group P2₁/c; for I: a = 7.053(3)Å, b = 9.389(3)Å, c = 15.488(4)Å, β = 91.60°, V = 1025.3(6)ų, Z = 4; for II: a = 10.650(4)Å, b = 15.062(5)Å, c = 7.412(4)Å, β = 104.20(3)°, V = 1152.6(8)ų, Z = 4. In both structures, the organic components act as bidentate ligands forming with AgNO₃ 34- and 14-membered topological rings, respectively. In complex I, the nearly tetrahedral environment of the Ag(I) atom is made up of the olefinic C=C bond, the O atoms of the nitrate anions, and the water molecule. 1-Allyloxybenzotriazole in structure II causes the deformation of the coordination polyhedron of Ag into a trigonal pyramid via inclusion of the ligand N atom in its coordination sphere. The topological units of the complexes form infinite polymer layers linked by anionic NO ₃ ^? bridges. In structure I, these layers are united through a system of hydrogen bonds into a three-dimensional framework.     

Molar heat capacity and thermodynamic properties of Lu(C5H9NO4)(C3H4N2)6(ClO4)3·5HClO4·10H2O

A complex of Lutetium perchloric acid coordinated with l-glutaminic acid (C₅H₉NO₄) and imidazole (C₃H₄N₂), Lu(C₅H₉NO₄)(C₃H₄N₂)₆(ClO₄)₃·5HClO₄·10H₂O was synthesized and characterized. Thermodynamic properties of the complex were studied with an adiabatic calorimeter (AC) from 80 to 390 K and differential scanning calorimetry (DSC) from 100 to 300 K. Two thermal abnormalities were discovered at 220.34 and 248.47 K, which were deduced to be phase transitions. One was interpreted as a freezing-in phenomenon of the reorientational motion of ClO₄ ^? ions and the other was attributed to the orientational order/disorder process of ClO₄ ^? ions. The low-temperature molar heat capacities were measured by AC and the thermodynamic functions [H _T  ? H _298.15] and [S _T  ? S _298.15] were derived in the temperature range from 80 to 390 K with temperature interval of 5 K. Thermal decomposition behavior of the complex was studied by thermogravimetric analysis and DSC.