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1.
Gas-phase electron diffractometry was used to study the molecular structure of N,N′-ethylenebis(salicylaldiminato)nickel(II), NiO2N2C16H14, [hereinafter Ni(salen)] at 583(5) K. The molecule has C 2 symmetry with a practically planar structure of the NiN2O2 coordination unit and with internuclear distances r α (Ni-O) = 1.882(21) Å and r α (Ni-N) = 1.889(22) Å. The results of B3LYP/CEP-31G molecular structure calculations are in good agreement with experimental data, whereas the RHF/CEP-31G method significantly overestimates the Ni-N internuclear distance and gives worse results for other structural parameters. According to 3LYP/CEP-31G calculations, the 1 A low-spin state is 28 kJ/mole lower in energy than the 3 B high-spin state.  相似文献   

2.
Two cis-dioxomolybdenum(VI) complexes [MoO2L] (L: L 1, 2 and L: L 2, 3) in a phenol-based sterically encumbered N2O2 ligand environment have been synthesized, and their crystallographic characterizations are reported. The orange crystals of 2 are monoclinic, space group P21/a with unit cell dimensions as a=16.2407(17) Å, b=7.2857(8) Å, c=18.400(2) Å, β=98.002(9)°, Z=4, and d cal=1.486 g cm?3. The light orange crystals of 3, however, are orthorhombic, space group, Pbcn, with unit cell dimensions a=8.3110(12) Å, b=12.637(3) Å, c=34.673(5) Å, Z=4, and d cal=1.187 g cm?3. The structures were refined by a full-matrix least-squares procedure on F 2 to a final R=0.046 (0.055 for 3) using 4944 (3677) all independent data. In both the cases, the Mo atom exists in a distorted octahedral geometry defined by a N2O4 donor set, which features a cis-Mo(–O)2 and a trans-Mo(OPh)2 arrangement. Compound 2 undergoes a quasireversible one-electron reduction at ?1.3 V vs Ag/AgCl reference due to MoVIO2/MoVO2 electron transfer and thus providing a rare example of steric solution to the comproportionation–dimerization problem encountered frequently in the development of valid biomimetic models for the active sites of oxomolybdenum enzymes.  相似文献   

3.
The single crystals of [UO2(C2O4){CONH2N(CH3)2}2] were synthesized and studied by X-ray diffraction. The crystals are monoclinic, a = 7.461(2) Å, b = 8.828(2) Å, c = 11.756(2) Å, β = 107.21(3)°, space group Pc, Z = 2, R = 2.94%. The structure comprises infinite chains [UO2(C2O4){CONH2N(CH3)2}2] extended along [001] and corresponding to the AT11M 2 1 crystallochemical group (A = UO 2 2+ , T11 = C2O 4 2? , M1 = N,N-CONH2N(CH3)2) of uranyl complexes. The chains are connected into a three-dimensional framework by hydrogen bonds involving the oxygen atoms of oxalate and uranyl ions and the N,N-dimethylcarbamide methyl groups.  相似文献   

4.
The coordination polymers [AgPF6(Me4Pyz)2] (I) and [AgPF6(2,3-Et2Pyz)2] (II) were synthesized, and their structures were determined. Crystals of I are monoclinic, space group C2/c, a = 10.213(2) Å, b = 16.267(3) Å, c = 12.663(3) Å, β = 92.90(3)°, V = 2102.1(7) Å3, ρcalcd = 1.660 g/cm3, Z = 4. The structure of I is built of polymeric zigzag [Ag(C8H12N2)] + chains and octahedral [PF6] anions. The coordination polyhedron of the Ag+ ion is a flat triangle. Crystals of II are tetragonal, space group P \(\bar 4\)2(1)/c,a = b = 10.641(1) Å, c = 18.942(1) Å, V = 2144.6(2) Å3, ρcalcd = 1.627 g/cm3, Z = 4. In the structure of II, 2D cationic layers of fused square rings exist; the rings consist of four Ag+ cations linked by four bridging ligands of diethylpyrazine Et2Pyz. The coordination polyhedron of the Ag+ ion is an irregular four-vertex polyhedron.  相似文献   

5.
The electrochemical properties of n-sulfonatothiacalyx[4]arene (H4XNa4) complexes with [Co(dipy)3]3+ and Fe3+ ions were studied by means of cyclic voltammetry in aqueous solution at pH 2.5. The observed single-electron reduction of [Co(dipy)3]3+ bound extraspherically to the upper rim and Fe3+ ion bound intraspherically to the lower rim of n-sulfonatothiacalyx[4]arene in binary [Co(dipy)3]3+ · H3X5?, H3X5? · Fe3+, and ternary [Co(dipy)3]3+ · H3X5? · Fe3+ heterometal complexes was more difficult than in the free state. The reversible single-electron transfer to the metal ion results in lower binding energy ([Co(dipy)3]3+, ΔΔG 0 = 3.9 kJ/mol) or in full fast dissociation of the complex (Fe3+). The ternary complex in the solution forms the aggregates, in which inner encapsulated Fe(III) and Co(III) ions are not reduced on the electrode. Their quantitative reduction takes place by the relay mechanism of intra- and intermolecular electron transfer through electrochemically generated [Co(dipy)3]2+ outer ions.  相似文献   

6.
The [Ir(NH3)5Cl]2[OsCl6]Cl2 binary complex salt has been prepared, and its structure was investigated by single crystal X-ray diffraction. Crystal data: a = 11.1901(13) Å, b = 7.9138(13) Å, c = 13.4384(18) Å; β = 99.640(3)°, V = 1190.0(2), space group C2/m, Z = 2, FW = 1099.47, d x = 3.068 g/cm3. Thermolysis products of [Ir(NH3)5Cl]2[OsCl6]Cl2, [Ir(NH3)5Cl][OsBr6], (NH4)2[OsCl6]x[IrCl6]1?x , and K2[OsCl6]x[IrCl6]1?x were studied by X-ray phase analysis; the unit cell parameters were refined, and the dependence of volume per atom (V/Z) on the composition of the Ir Os1?x solid solution has been plotted.  相似文献   

7.
Single crystals of two new mercury thiohalides of the composition Hg3S2Cl2? xBrx(x = 0.5) have been grown from gas phase and studied by X-ray crystallography. Structure refinement for monoclinic (I) and cubic (II) phases (I: a = 16.841(2) Å, b = 9.128(2) Å, c = 9.435(4) Å; β = 90.080(10)°, V = 1450.3(7) Å3, space group C2/m, Z = 8, R = 0.0528; II: a = 18.006(2) Å, V = 5837.8(11) Å3, space group \(Pm\bar 3n\), Z = 32, R = 0.0503) clearly shows that they are polymorphs of the same composition Hg3S2Cl1.5Br0.5. The monoclinic modification I is similar to the synthetic phases γ-Hg3S2Cl2, β-Hg3S2Br2, Hg3Se2Br2 and to the analogue of radtkeite mineral, Hg3S2ClI. The modification II is isostructural to the synthetic β-Hg3S2Cl2. In both structures, each S atom coordinates three Hg atoms with the formation of pyramidal SHg3 units (Hg-S 2.37–2.48 Å; HgSHg 93.1–97.5 ). The SHg3 units are linked through Hg vertices into corrugated layers [Hg12S8]∞∞ (I) and isolated cubic groups [Hg12S8] (II). Similarly to other mercury chalcohalides, the crystal structures are basically determined by the halogen atoms which form a cubic sublattice incorporating the Hg-S moieties.  相似文献   

8.
The crystal structure of As-schwatzite Cu6(Cu5.26Hg0.75)(As2.83Sb1.17)S13 (Aktash deposit, Altai mountains) is refined. Tetrahedrally shaped dark-gray single crystals of the mineral belong to the cubic crystal system: I4¯3m space group, a = 10.2890(1) Å, V = 1089.2(1) Å3, d = 4.99 g/cm3, Z = 2 for the composition Cu11.26Hg0.75As2.83Sb1.17S13, R = 0.0177. The structure is based on the sphalerite-like framework comprising identically oriented (Cu,Hg)S4 tetrahedra ((Cu,Hg)-S 2.3452(8) Å) and (As,Sb)S3 pyramids ((As,Sb)-S 2.311(1) Å) sharing their vertices. The centers of [Cu6] octahedra in the (000) and (1/2 1/2 1/2) positions coinciding with the centers of the “cluster” anionic vacancies [□]4 are occupied by the so-called “thirteenth” sulfur atom. Quantum chemical calculations of the electron density are carried out for the [As4S13Cu6]6 fragment. The calculation results confirm the presence of strain in the [As4S13Cu6]6 moiety, which exists due to the support of the surrounding symmetric framework including the external sulfur atoms of the fragment. The possibility of inclusion of mercury into the framework, which is much richer in arsenic than in antimony, is demonstrated. High stability of the framework determines significant compression of the S-centered [SCu6] octahedron in its interstices, bringing together copper atoms to 3.145(1) Å and shortening the Cu-S distances to 2.224(1) Å  相似文献   

9.
The crystal structure of the compound OsSe2Br12 obtained by the reaction of OsBr4 with SeBr4 or Se in liquid bromine at 100°C was studied by X-ray powder diffraction. The structure of osmium selenobromide corresponds to a specific type: space group C2/m, a = 14.0464(2) Å, b = 11.05398(14) Å, c = 6.50340(9) Å, β = 112.2645(11)°, Z = 2; R B = 0.03946, R wp = 0.05403, χ2 = 4.261 for 479 reflections and 53 refinement parameters. The X-ray diffraction analysis confirmed the earlier assumption concerning the cation-anion structure of the compound representing a packing of nearly regular [OsBr6]2? octahedra as anionic complexes and deficient [:SeBr3]+ tetrahedra as cationic complexes in which the missing vertex is occupied by the lone electron pair of selenium.  相似文献   

10.
The structures of three novel octahedral rhenium cluster compounds [Re6S8(CN)2(py)4]·H2O (1), [Re6S8(CN)2(4-Mepy)4] (2), [Re6S8(CN)2(4-Mepy)4]·4-Mepy (3) (py = pyridine, 4-Mepy = 4-methylpyridine) are determined by X-ray crystallography. Crystal data are: C2/m space group, a = 14.813(1) Å, b = 14.772(1) Å, c = 9.2122(6) Å, β = 119.085(2)°, V = 1761.7(2) Å3, d x = 3.318 g/cm3, R = 0.0585 (1); I41/amd space group, a = 16.0018(3) Å, c = 14.7186(5) Å, V = 3768.81(16) Å3, d x = 3.169 g/cm3, R = 0.0489 (2); P21/c space group, a = 9.0452(4) Å, b = 15.8065(7) Å, c = 15.2951(6) Å, β = 103.700(2)°, V = 2124.57(16) Å3, d x = 2.957 g/cm3, R = 0.0245 (3). Molecular cluster complexes interact via π-π stacking affording 3D frameworks in 1 and 2 and chains in 3.  相似文献   

11.
Powder and single crystal X-ray diffraction studies have been performed for anhydrous nitrate complexes Rb2[Pd(NO3)4] (I) and Cs2[Pd(NO3)4] (II). Crystal data for I: a = 7.843(1) Å, b = 7.970(1) Å, c = 9.725(1) Å; β = 100.39(1)°, V = 597.9(1) Å 3, space group P21/c, Z = 2, d calc = 2.918 g/cm3; for II: a = 10.309(2) Å, b = 10.426(2) Å, c = 11.839(2) Å; β = 108.17(3)°, V = 1209.0(4) Å3, space group P21/c, Z = 4, d calc = 3.408 g/cm3. The structures are formed by isolated [Pd(NO3)4]2? complex anions and alkali metal cations. The plane-square environment of the Pd atom is formed from the oxygen atoms of the monodentate nitrate groups. The geometrical characteristics of the complex anions are analyzed. Compound II has a short contact Pd...Cs 3.252 Å.  相似文献   

12.
The preparation of EnH2[IrCl6] is described. Crystal data for C2H10Cl6IrN2 are: a = 6.8972(11) Å, b = 6.9435(16) Å, c = 7.3354(11) Å; α = 88.269(3)°, β = 65.495(2)°, γ = 60.305(2)°, V = 270.76(9) Å3, space group P1, Z = 1, dcalc = 2.864 g/cm3. Crystal chemical analysis of the general motif of the structure was performed by the translation sublattice identification technique. It has been found that complex anions [IrCl6]2? follow the nodes of a rather regular rhombohedral subcell with the parameters ac = 7.1 Å, αc = 64°.  相似文献   

13.
A supramolecular adduct of gadolinium aqua nitrato complex and cucurbit[6]uril { [Gd(NO3)(H2O)7](C5H5N)@(C36H36N24O12)}(NO3)2·10H2O is obtained by slow diffusion of methanol into an aqueous solution containing gadolinium nitrate, pyridine, and cucurbit[6]uril. According to single crystal X-ray diffraction data, water molecules coordinated to metal atom make hydrogen bonds to polarized carbonyl groups of the macrocycle. The heptaaquanitratogadolinium(III) [Gd(NO3)(H2O)7]2+ cation is structurally characterized for the first time. Crystal system is triclinic, space group \(P\overline 1 \), a = 12.3137(4) Å, b = 14.2334(5) Å, c = 19.5629(6) Å; α = 80.850(1)°, β = 86.879(1)°, γ = 68.855(1)°; V = 3157.15(18) Å3, Z = 2. Oriented hydrogen-bonded chains of alternating cucurbit[6]uril molecules and gadolinium aqua cations form in the crystal structure.  相似文献   

14.
A novel one-dimensional chain complex [Cd(NITpPy)2(N(CN)2)2)] n (NITpPy = 2-(4′-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) has been synthesized and characterized structurally. It crystallizes in the triclinic space group P \(\bar 1\) with a = 7.1742(13), b = 9.4913(17), c = 13.208(2) Å, α = 71.020(2)°, β=87.308(2)°, γ = 70.503(2)°, V = 799.8(3) Å3, C28H32CdN12O4, Mr = 713.06, Z = 1, ρ c = 1.48 g/cm3, μ(MoK α) = 0.736 mm?1, F(000) = 364, R = 0.0275 and wR = 0.0605 for 2702 observed reflections with I > 2σ(I). The crystal structure consists of infinite chains of [Cd(NITpPy)2(N(CN)2)2)] units linked by dicyanamide anions [N(CN)2]?. Each Cd2+ ion is six-coordinated with the geometry of a distorted octahedron.  相似文献   

15.
The crystal structures of two polymorphs of molybdenyl salicylidene-2-furfuryliminate [MoO2(L1)2] have been solved by X-ray diffraction. Both complexes crystallize in centrosymmetric and non-centrosymmetric space groups (P21/c and Р21, respectively) of monoclinic system and have similar structures and close geometric parameters. The Мо atoms have a distorted octahedral coordination to two terminal oxo ligands in cis-positions to each other and two pairs of the oxygen atoms (cis- to О(oxo)) and the nitrogen atoms (trans- to О(oxo)) of two bidentate chelate ligands (L1).  相似文献   

16.
The crystal structure of europium cinnamate of the composition [Eu(Cin)3] n (Cin is cinnamic acid anion C9H7O 2 ? ) was determined by X-ray crystallography (a = 22.626(1) Å, c = 7.7330(7) Å, space group R3/c, Z = 3, ρcalc = 1.448 g/cm3). The coordination polyhedron of Eu atoms is a distorted trigonal prism with three centered square faces. The structure is built of infinite polymeric chains [Eu(Cin)3] n running along the c axis and linked by van der Waals and π stacking interactions. Luminescent characteristics of the compound were determined.  相似文献   

17.
The reaction of cyclopentylamine with 2-hydroxy-1-naphthaldehyde and 5-nitrosalicylaldehyde, respectively, in methanol affords two new Schiff bases, 1-(cyclopentyliminomethyl)naphthalen-2-ol (HL1) and 4-nitro-2-(cyclopentyliminomethyl)phenol (HL2). Two new zinc(II) complexes, [Zn(L1)2] (I) and [Zn(L2)2] (II), derived from the Schiff bases, have been prepared and characterized by single-crystal X-ray diffraction, FT-IR, and elemental analysis. Complex I crystallizes in the monoclinic space group P21/c with a = 17.834(4), b = 14.738(3), c = 9.868(2) Å, β = 91.20(3)°, V = 2593.1(9) Å3, Z = 4. Complex II crystallizes in the triclinic space group P \(\bar 1\) with a = 10.206(1), b = 10.502(1), c = 12.554(1) Å, α = 66.771(2)°, β = 78.133(2)°, γ = 76.292(2)°, V = 1191.8(1) Å3, Z = 2. The Zn atom in each complex is coordinated by two N and two O atoms from two Schiff base ligands, forming a tetrahedral geometry. The Schiff bases and the complexes were assayed for antibacterial activities.  相似文献   

18.
A new complex [UO2CrO4{CH3CON(CH3)2}2] (I) was studied by thermal analysis, IR spectroscopy, and X-ray crystallography. The crystals are monoclinic: a = 13.8108(11) Å, b = 8.6804(7) Å, c = 13.0989(10) Å, β = 104.777(1)°, V = 1518.4(2) Å3, space group P21/c, Z = 4, R = 2.39%. The structure of I contains infinite chains of the [UO2CrO4{CH3CON(CH3)2}2] composition running along [001]; the complex belongs to the AT11M1 2 crystal-chemical group (A = UO 2 2+ , T11 = CrO 4 2? , M1 = CH3CON(CH3)2) of uranyl complexes. The chains are linked into a three-dimensional framework due to hydrogen bonds between oxygen atoms of chromate ions and hydrogen atoms of methyl groups of the dimethylacetamide.  相似文献   

19.
Novel complex salts [Au(en)2]Cl(ReO4)2 (I) and [Au(en)2](ReO4)3 (II), en = ethylenediamine, are obtained. Their crystal structures are determined by single crystal X-ray diffraction. Complex I crystallizes in the triclinic crystal system: a = 6.2172(7) Å, b = 7.1644(8) Å, c = 8.8829(8) Å, α = 96.605(4)°, β = 110.000(4)°, γ = 97.802(4)°, P-1 space group, Z = 1, d x = 3.905 g/cm3; complex II crystallizes in the monoclinic crystal system: a = 15.244(2) Å, b = 7.6809(8) Å, c = 9.3476(12) Å, β = 127.004(3)°, C2 space group, Z = 4, d x = 4.057 g/cm3.  相似文献   

20.
The present research work reports the study on crystal structure, vibrational spectroscopy and thermal analysis of organic-inorganic hybrid compound (C6H5(CH2)2NH3)2CdCl4. Single crystals of bis(phenethylammonium)tetrachlorocadmate (C6H5(CH2)2NH3)2CdCl4 (PEA–Cd) were obtained by diffusion at room temperature. This compound crystallizes in the orthorhombic space group C2cb with unit cell parameters a = 7.4444(2) Å, b = 38.8965(3) Å, c = 7.3737(2) Å and Z = 4. Single crystal structure has been solved and refined to R = 0.036 and wR = 0.092. The structure consists of an extended [CdCl4]2– network and two [C6H5(CH2)2NH3]+ cations to form a two-dimensional perovskite system. The infrared (IR) spectrum of the title compound was recorded at room temperature. Differential scanning calorimetry (DSC) was used to investigate the phase transition; this compound exhibits a reversible single solid-solid phase transition.  相似文献   

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