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1.
By adding piperazine to a hydrofluoric and phosphoric acid solution of Manganese(III) fluoride, the fluoride phosphate (pipzH2)[MnF2(HPO4)(H2O)](H2PO4) can be crystallized. Its structure is built by piperazinium(2+) cations, (H2PO4)? anions, and an anionic double‐chain of [HPO4] tetrahedra and [MnO3F2(H2O)] octahedra. The structure is triclinic, space group P , Z = 2, a = 622.97(4), b = 923.46(6), c = 1183.62(7) pm, α = 98.343(6)°, β = 100.747(7)°, γ = 107.642(5)°, R = 0.0289. It is worth noting that a ferrodistortive Jahn‐Teller order is observed with [MnO3F2(H2O)] octahedra strongly elongated along the F–Mn–OH2 axes perpendicular to the chain plane. The structure is stabilized by very strong hydrogen bonds.  相似文献   

2.
The crystal structures of three new diaqua-tetrafluoro-manganate(III) compounds with different organic N-cations have been determined: 2-picoH[MnF4(H2O)2] 1 (2-pico = 2-methyl-pyridine), space group P21/c, a = 9.439, b = 13.662, c = 7.641 Å, β = 91.31°; R = 0.059; TMEDAH2[MnF4(H2O)2]2 2 (TMEDA = N,N,N′,N′-tetramethyl ethane diamine), space group P21/c, a = 5.421, b = 15.970, c = 9.677 Å, β = 96.37°, R = 0.031, and TMBDAH2[MnF4(H2O)2]2 3 (TMBDA = N,N,N′,N′-tetramethyl-1,4-butane-diamine), space group P21/n, a = 12.631, b = 5.577, c = 12.976 Å, β = 98.10°, R = 0.040. All three compounds show 2 D H-bonding networks of [MnF4(H2O)2] anions separated by the organic cations. However, the topology of the anionic H-bonding nets is different for each compound. The anions are strongly elongated by the Jahn-Teller effect and are arranged in a ferrodistortive way in compounds 1 and 2 , whereas in compound 3 the arrangement is described as in a herringbone-like antiferrodistortive variant.  相似文献   

3.
Organic–inorganic hybrid material of formula (C4H3SC2H4NH3)2[PbI4] was synthesized and studied by X-ray diffraction, Infrared absorption, Raman scattering, UV–Visible absorption and photoluminescence measurements. The molecule crystallizes as an organic–inorganic two-dimensional (2D) structure built up from infinite PbI6 octahedra surrounded by organic cations. Such a structure may be regarded as quantum wells system in which the inorganic layers act as semiconductor wells and the organic cations act as insulator barriers. Room temperature IR and Raman spectra were recorded in the 520–3500 and 10–3500 cm−1 frequency range, respectively. Optical absorption measurements performed on thin films of (C4H3SC2H4NH3)2[PbI4] revealed three distinct bands at 2.4, 2.66 and 3.25 eV. We also report DFT calculations of the electric dipole moments (μ), polarizability (α), the static first hyperpolarizability (β) and HOMO–LUMO analysis of the title compound investigated by GAUSSIAN 09 package. The calculated static first Hyperpolarizability is equal to 11.46 × 10−31 esu.  相似文献   

4.
This article presents a combined experimental and computational study of [Cu(tppz)(SCN)2], where ttpz stands for 2,3,5,6-tetra-(2-pyridyl)pyrazine. The compound has been studied by IR, UV–Vis spectroscopy, and single crystal X-ray analysis. The geometry around copper atom may be described as a distorted square pyramid. The equatorial plane is defined by three nitrogen atoms of tppz and one nitrogen atom of thiocyanate group. The apical site is occupied by nitrogen atom of the second SCN? ion. The electronic spectrum of [Cu(tppz)(SCN)2] was analyzed, and bands were assigned through the DFT/TDDFT procedures.  相似文献   

5.
A new iron(III) arsenate templated by ethylenediamine, (C2H10N2) [Fe(HAsO4)2(H2AsO4)](H2O), has been prepared by hydrothermal synthesis. The unit-cell parameters are a = 8.705(3) A, b = 16.106(4) A, c = 4.763(1) A, beta = 90.63(3) degrees; monoclinic, P2(1) with Z = 2. The compound exhibits a chain structure along the c-axis with the ethylenediammonium cations as counterion. The chains show isolated FeO6 octahedra with two HAsO4 and one H2AsO4 tetrahedra per FeO6 octahedron. The ESR spectrum at 5.0 K is isotropic with a g-value of 2.0, which remains practically unchanged at room temperature. Magnetic measurements indicate the presence of antiferromagnetic interactions. A value of -0.835 K for the J-exchange parameter has been calculated by fitting the magnetic data to a model for antiferromagnetic chains of spin S = 5/2.  相似文献   

6.
合成了4个新型的稀土化合物(C26H40N2O4)[Ln(NO3)5H2O](Ln=Pr,Nd,Sm,Eu),采用元素分析和红外光谱表征,用四圆衍射仪测定了其中(C26H40N2O4)[Eu(NO3)5H2O]的晶体结构,属三斜晶系,P1空间群,晶胞参数:α=0.9100(4)nm,b=1.3560(3)nm,c=1.6463(4)nm;α=68.62(2)°,β=74.84(3)°,γ=87.50(2)°;Z=2.中心铕离子由5个硝酸根的10个氧原子和1个水分子中的氧原子配位,配位数是11.1,7,10,16-四氧-4,13-二氮杂-N,N'-二苄基环十八烷(N,N'-二苄基穴醚(2,2))未参与配位.  相似文献   

7.
8.
A new organic-inorganic hybrid polyoxometalate based on Dawson-like polyoxotungstate anion [SbW18O60]9-, formulated [Co(2,2'-bpy)3]2[Co(2,2'-bpy)2Cl][Co(2,2'-bpy)2]H2[SbW18O60]·4H2O (2,2'-bpy= 2,2(-bipyridine) has been synthesized from Sb2O3, Na2WO4, CoCl2, and 2,2'-bipyridine materials by hydrothermal method, and which was characterized by elemental analyses, IR, XPS, EPR, TG, and X-ray single crystal diffraction. Structure analysis shows that the polyoxoanion self-assembled under hydrothermal conditions consists of a Dawson-like polyoxotungstate cluster anion [SbW18O60]9- encapsulating a pyramidal {SbO3} group within the {W18} cluster cage. EPR spectra show that the high-spin octahedral CoⅡ and low-spin CoⅡ ions coexist in the title compound. Magnetic properties indicate that the compound is antiferromagnetic.  相似文献   

9.
The [ReCl3(MeCN)(PPh3)] complex reacts with 1-isoquinolinyl phenyl ketone (N–O) to give [ReCl3(N–O)(PPh3)]. The compound has been studied by IR, UV–Vis spectroscopy, magnetic measurements and X-ray crystallography. The magnetic behavior is characteristic of mononuclear octahedral Re(III) complex with d4 low-spin (3T1g ground state) and arises because of the large spin–orbit coupling, which gives diamagnetic ground state. The molecular orbital diagram of [ReCl3(N–O)(PPh3)] has been calculated with the density functional theory (DFT) method, and time-dependent DFT (TD-DFT) calculations have been employed in order to discussion of its spectroscopic properties in more detail.  相似文献   

10.
A combined experimental and computational study of the dinuclear rhenium(V) complex containing (ReO)2(µ-O) core is presented in this article. The solid-state [Re2Cl4(O)2(µ-O)(3,5-lut)4] (3,5-lut = 3,5-dimethylpyridine) complex was characterised structurally (by single crystal X-ray diffraction) and spectroscopically (by IR, NMR, UV-VIS). The electronic structure was examined using the density functional theory (DFT) method. The spin-allowed electronic transitions were calculated using the time-dependent DFT method, and the UV-VIS spectrum was discussed.  相似文献   

11.
The X-ray structure of Cs(2)[Ni(CN)(4)].H(2)O and the polarized single-crystal UV absorbance spectra of Cs(2)[Ni(CN)(4)].H(2)O and Cs(2)[Pt(CN)(4)].H(2)O are presented. The two complexes are isostructural, with helical arrangements of M(CN)(4)(2)(-) ions in which there is moderate metal-metal electronic perturbation resulting in a spectral red shift from solution in the UV absorbance spectra. In addition, we have modeled the nickel system with a ZINDO calculation of a three-molecule segment of the helix and have found remarkably good agreement with experiment, including excellent reproduction of the red shift. Crystal data are as follows: Cs(2)[Ni(CN)(4)].H(2)O, hexagonal, space group P6(1), a = 9.5260(10) A, c = 19.043(2) A, V = 1496.5(3) A(3), T = 100 K, Z = 6, 4335 observed data, R = 0.016, R(w) = 0.034.  相似文献   

12.
13.
The title compound (4,4'-H2bipy)[CdBr4]·H2O 1 has been synthesized via hydrothermal reaction and characterized by X-ray diffraction. The crystal belongs to monoelinic,space group P21/c with a=8.260(3), b=23.926(7), c=9.774(2) (A), β=106.777(9)°,C10H12Br4CdN2O, Mr=608.26, V=1849.4(9)(A)3, Z=4, Dc=2.185 g/cm3, S=1.005, μ(MoKα)=9.814 mm-1, F(000)=1128, R=0.0646 and wR=0.0989. The crystal structure analysis of 1reveals that the title compound features an isolated structure, based on discrete 4,4'-H2bipy moieties and lattice water molecules which are linked by hydrogen bonds together with tetrahedral cadmium atoms terminally coordinated by four bromine atoms.  相似文献   

14.
[ReCl3(MeCN)(PPh3)2] reacts with bis(3,5-dimethypyrazol-1-yl)methane (bdmpzm) in acetone to give [ReCl3(bdmpzm)(PPh3)]. The compound has been studied by IR, UV–Vis spectroscopy and X-ray crystallography. The molecular orbital diagram of [ReCl3(bdmpzm)(PPh3)] has been calculated with the density functional theory (DFT) method.  相似文献   

15.
在二甲亚砜(DMSO)中, 以MnCl2.2H2O和K3[Cr(Ox)3].3H2O为原料, 合成了离子型配合物[Mn(phen)2(H2O)2]2[Cr(OX)3][HOCH2CH2O].4H2O。晶体结构测定表明, 该晶体属单斜晶系, P2/c空间群。晶体学参数: a=1.0602(3),b=1.3515(3), c=2.1508(3)nm, β=102.57(2)°, V=3.008(1)nm^3, Z=2,Dc=1.49g/cm^3, F(000)=1392。最后的偏差因子R=0.067。测定了化合物的UV-Vis-NIR, IR, XPS, ESR光谱和变温磁化率, 讨论了相应的性质。  相似文献   

16.
Exchange mechanisms and magnetic structure in the two-dimensional cyano-bridged molecule-based magnet K2[Mn(H2O)2]3[Mo(CN)7]2.6H2O have been investigated by a combination of neutron diffraction studies on both single crystal and powder samples and theoretical DFT calculations. The experimental spin density has been deduced from a new refinement of previously obtained polarized neutron diffraction (PND) data which was collected in the ordered magnetic state at 4 K under a saturation field of 3 T performed in the C2/c space group, determined by an accurate re-evaluation of the X-ray structure. Positive spin populations were observed on the two manganese sites, and negative spin populations were observed on the molybdenum site, which provides evidence of antiferromagnetic Mo3+-Mn2+ exchange interactions through the cyano bridge. The experimental data have been compared to the results of DFT calculations. Moreover, theoretical studies reveal the predominance of the spin polarization mechanism in the Mo-C-N-Mn sequence, with the antiferromagnetic nature of the interaction being due to the overlap between the magnetic orbitals relative to manganese and molybdenum in the cyano bridging region. The magnetic structure of K2[Mn(H2O)2]3[Mo(CN)7]2.6H2O has been solved at low temperature in zero field by powder neutron diffraction measurements. The structure was found to be ferrimagnetic where the manganese and molybdenum spins are aligned along the axis in opposite directions.  相似文献   

17.
The reaction between (NH4)[MoBr5 · H2O] and pyridine in acetonitrile (CH3CN) at room temperature results in the mixture of cis- and trans-(pyH)[MoBr4py2] which can be separated on the basis of solubility. cis-M[MoBr4py2] · ? H2O (M = NH4+, Rb+, Cs+), cis-(bipyH)[MoBr4py2] (bipy = 2,2′-bipyridil) and cis-(PPh4)[MoBr4py2], were prepared from cis-(pyH)[MoBr4py2]. At the temperature of boiling acetonitrile irreversible cis to trans isomerisation takes place. Bromine oxydizes cis isomers at room temperature to trans-MoBr4py2. The compounds were characterised by chemical analysis, infrared, UV-VIS spectroscopy, conductivity measurements and powder diffraction. The crystal structure of cis-(NH4)[MoBr4py2] · ? H2O has been determined: rhombohedral, R3c, (No. 161), a = 15.809(3) Å, β = 112.79(2)°, Z = 6, DC = 2.29, DO = 2.27(3) g/cm3, V = 2 601(1) Å3, R1 = 0.046, Rw = 0.068. Average Mo? Br and Mo? N(pyridine) distances within the anion are 2.58(2) and 2.20(2) Å. cis-Rb[MoBr4py2] · ? H2O and cis-Cs[MoBr4py2] · ? H2O are isostructural with cis-(NH4)[MoBr4py2] · ? H2O.  相似文献   

18.
Two hydroxo-bridged complexes, {[Mn(III)(3-CH(3)O)salen](2)[Cr(III)(salen)(OH)(2)]}ClO(4)·6H(2)O (1) and {[Mn(III)(5-CH(3))salen](2)(OH)}ClO(4)·3H(2)O (2) [salen = N,N'-ethylenebis(salicylideneiminato) dianion], have been synthesized by the hydrolysis of the corresponding Mn(III)(Schiff-Bases) derivatives and [Cr(salen)(H(2)O)(2)]Cl precursors. X-Ray structure characterization reveals the discrete linear arched trinuclear structure of 1 and the 1D chain arrangement of 2. Magnetic experimental data and density functional theory (DFT) calculations both indicate the dominant antiferromagnetic interaction mediated by the hydroxo-bridges in both 1 and 2. Frequency-dependent AC susceptibilities reveal slow relaxation of 1 in low temperature. It is worth noting that the structure and magnetic properties of 1 is comparable to a reported cyano-bridged SMM, K[(5-Brsalen)(2)(H(2)O)(2)Mn(2)Cr(CN)(6)]·2H(2)O.  相似文献   

19.
20.
The reaction of copper(II) nitrate trihydrate and 2-(2-pyridyl)benzimidazole (pybzim) leads to [Cu(pybzim)2(NO3)](NO3). The compound has been studied by IR, UV–Vis spectroscopy and X-ray crystallography. The electronic structure of the [Cu(pybzim)2(NO3)]+ cation has been calculated with the density functional theory (DFT) method. The spin-allowed doublet–doublet electronic transitions of [Cu(pybzim)2(NO3)]+ have been calculated with the time-dependent DFT method, and the UV–Vis spectrum of the title compound has been discussed on this basis.  相似文献   

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