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1.
2.
The pale‐pink, hygroscopic compounds Mn(OH)X (X = Br, I) were obtained by high‐pressure synthesis in a Walker‐type multianvil apparatus. They crystallize in the space group P21/c with a = 640.48(3), b = 698.80(3), c = 615.54(2) pm, β = 110.30(1)° at 183(1) K (X = Br), and a = 686.18(3), b = 713.08(3), c = 637.18(3) pm, β = 109.51(1)° at 150(1) K (X = I). The crystal structures are isotypic to Cu(OH)Cl and consist of edge‐sharing distorted Mn(OH)3X3 octahedra arranged in sheets parallel to the bc‐plane. Spin‐polarized scalar‐relativistic DFT+U calculations predict an intrinsic magnetic insulating state (ca. 3.5 eV bandgap) that is proximate to frustration. Calculated effective magnetic moments equal to 4.34 μB/f.u. for Mn(OH)Br and 4.33 μB/f.u. for Mn(OH)I. FT‐IR spectroscopy confirmed interlayer hydrogen bonding. As a side result of the experiments, the compound trans‐MnBr2 · 4H2O was obtained. It crystallizes in the space group Cmcm with a = 438.64(2), b = 1167.84(6), and c = 730.95(4) pm.  相似文献   

3.
High‐pressure modifications of the rare earth oxide fluorides REOF (RE = Pr, Nd, Sm – Gd) were successfully synthesized under conditions of 11 GPa and 1200 °C applying the multianvil high‐pressure/high‐temperature technique. Single crystals of HP‐REOF (RE = Nd, Sm, Eu) were obtained making it possible to analyze the products by means of single‐crystal X‐ray diffraction. The compounds HP‐REOF (RE = Nd, Sm, Eu) crystallize in the orthorhombic α‐PbCl2‐type structure (space group Pnma, No. 62, Z = 4) with the parameters a = 632.45(3), b = 381.87(2), c = 699.21(3) pm, V = 0.16887(2) nm3, R1 = 0.0156, and wR2 = 0.0382 for HP‐NdOF, a = 624.38(3), b = 376.87(2), c = 689.53(4) pm, V = 0.16225(2) nm3, R1 = 0.0141, and wR2 = 0.0323 for HP‐SmOF, and a = 620.02(4), b = 374.24(3), c = 686.82(5) pm, V = 0.15937(2) nm3, R1 = 0.0177, and wR2 = 0.0288 for HP‐EuOF. Calculations of the bond valence sums clearly showed that the oxygen atoms occupy the tetrahedrally coordinated position, whereas the fluorine atoms are fivefold coordinated in form of distorted square‐pyramids. The crystal structures and properties of HP‐REOF (RE = Nd, Sm, Eu) are discussed and compared to the isostructural phases and the normal‐pressure modifications of REOF (RE = Nd, Sm, Eu). Furthermore, results of investigations by EDX and Raman measurements including quantum mechanical calculations are presented.  相似文献   

4.
The new polymorph of sodium tetraborate HP‐Na2B4O7 was synthesized under high‐pressure / high‐temperature conditions of 6 GPa and 1000 °C in a multianvil apparatus with a Walker‐type module. HP‐Na2B4O7 crystallizes with nine formula units per cell in the trigonal chiral space groups P3221 or P3121. The parameters are a = 765.5(2), c = 2142.3(4) pm, V = 1.0872(3) nm3, R1 = 0.0581, and wR2 = 0.0809 (all data). The crystal structure of HP‐Na2B4O7 is built up from interconnected “sechser” rings of alternating corner‐sharing BO3 and BO4 groups.  相似文献   

5.
Ping Li  Zhihong Liu 《中国化学》2012,30(4):847-853
A new hydrated lithium borate, Li4[B8O13(OH)2]·3H2O, has been hydrothermally synthesized and characterized by single crystal X‐ray diffraction, FT‐IR spectroscopy, simultaneous TGA‐DTA and chemical analysis. It crystallizes in the triclinic, space group , a=8.4578(5) Å, b=8.7877(5) Å, c=10.8058(7) Å, α=87.740(3)°, β=71.819(3)°, γ=61.569(3)°, Z=2, V=665.26(7) Å3, Dc=2.043 g/cm3. Its crystal structure features polyborate anionic layers with the larger odd 13‐membered boron rings constructed by [B8O13(OH)2]4? FBBs. Through designing the thermochemical cycle, the standard molar enthalpy of formation of this borate was determined to be ?(7953.8±6.6) kJ·mol?1 by using a heat conduction microcalorimeter.  相似文献   

6.
利用水热法合成了两种过渡金属配合物为模板剂的含水硼酸盐晶体Co(en)3[B4O5(OH)4]Cl·3H2O(1) 和 [Ni(en)3][B5O6(OH)4]2·2H2O (2),并通过元素分析、X射线单晶衍射、红外光谱及热重分析对其进行了表征。化合物1晶体结构的主要特点是在所有组成Co(en)33+, [B4O5(OH)4]2–, Cl– 和 H2O之间通过O–H…O、O–H…Cl、N–H…Cl和N–H…O四种氢键连接形成网状超分子结构。化合物2晶体结构的特点是[B5O6(OH)4]–阴离子通过O–H…O氢键连接形成沿a方向有较大通道的三维超分子骨架,模板剂[Ni(en)3]2+阳离子和结晶水分子填充在通道中。  相似文献   

7.
1 INTRODUCTION At present the researches on more efficient solid-state laser materials become more important for the rapid development of diode-laser pumped solid-state laser. More researches have been devoted to the double borate compounds RX3(BO3)4 (R = Y, La, Gd and X = Y, Al, Sc), some of which exhibit good chemical and physical properties[1~10]. The rare earth and alkali-halide double borates M3Ln2(BO3)4 (M = Ca, Sr, Ba and Ln = LaLu and Y) were reported in literatures[11…  相似文献   

8.
The system CuO/In2O3/P2O5 has been investigated using solid state reaction between CuO, In2O3 and (NH4)2HPO4 in silica glass crucibles at 900 °C. The powder samples were characterized by X‐ray diffraction, thermal analysis and FT‐IR spectroscopy. Orange single crystals of the new quaternary phase were achieved by the process of crystallization with mineralizers in sealed silica glass ampoules. They were then analyzed with EDX and single‐crystal X‐ray analysis in which the composition Cu8In8P4O30 with the triclinic space group P$\bar{1}$ (No 2) with a = 7,2429(14) Å, b = 8,8002(18) Å, c = 10,069(2) Å, α = 103,62(3)°, β = 106,31(3)°, γ = 101,55(3)° and Z = 1 was found. The three‐dimensional framework consists of [InO6] octahedra and distorted [CuO6] octahedra, overcaped [InO7] prisms and [PO4] tetrahedra, also trigonal [(CuIn)O5] bipyramids and distorted [(CuIn)O6] octahedra, where copper and indium are partly exchanged against each other. Cu8In8P4O30 exhibits an incongruent melting point at 1023 °C.  相似文献   

9.
The reaction of chlorosulfonyl isocyanate (ClSO2NCO) with anhydrous hydrogen fluoride (aHF) leads to the formation of ClSO2NHC(O)F. The title compound with a melting point of –38 °C is characterized by vibrational spectroscopy and a single crystal structure analysis. It crystallizes in the tetragonal space group I41/a with 16 formula units per unit cell. a = 11.1115(2) Å, c = 16.5654(6) Å. The experimental data are supported by quantum‐chemical calculations on the PBE1PBE/6‐311G(3pd,3df) level of theory.  相似文献   

10.
Gadolinium disulfide was prepared by high‐pressure synthesis at 8 GPa and 1173 K. It crystallizes in the monoclinic space group P121/a1 (No. 14) with lattice parameters a = 7.879(1) Å; b = 3.936(1) Å, c = 7.926(1) Å and β = 90.08(1)°. The crystal structure is a twofold superstructure of the aristotype ZrSSi and consists of puckered cationic [GdS]+ double slabs that are sandwiched by planar sulfur sheets containing S22– dumbbells. The thermal decomposition of GdS2 proceeds via the sulfur‐deficient polysulfides GdS1.9, GdS1.85 and GdS1.77 and eventually results in the sesquisulfide Gd2S3. GdS2 is a paramagnetic semiconductor which orders antiferromagnetically at TN = 7.7(1) K. A metamagnetic transition is observed in the magnetically ordered state.  相似文献   

11.
The new zinc borate Zn3B4O9 was synthesized at high-pressure/high-temperature conditions of 10 GPa and 1173 K in a Walker-type multianvil pressure device. It crystallizes in the space group P (no. 2) with a=5.5028(2) Å, b=6.7150(3) Å, c=7.8887(3) Å, α=83.99(1)°, β=73.38(1)°, γ=74.75(1)°, V=269.35(2) Å3, and two formula units (Z=2) per unit cell. The structure was confirmed via single-crystal X-ray diffraction. Zn3B4O9 can be synthesized phase pure, which is shown with a Rietveld refinement. IR-spectroscopic data of a powder sample were collected.  相似文献   

12.
The crystal structure of Li2B4O7 was studied by single crystal X‐ray diffraction whilst the substance was cooled down from room temperature to ?150 °C. The title compound crystallizes in the tetragonal, non‐centrosymmetric space group I 41cd (no. 110), a = 9.475(5) Å (r.t.), c = 10.283(6) Å (r.t.), R values for seven different data sets vary from 2.6 to 2.9 %. Low‐temperature single crystal examinations were combined with low‐temperature powder X‐ray diffraction experiments (?189 – +27 °C). The results are discussed in comparison with data earlier obtained at high temperatures (20 – 500 °C). No phase transitions or abrupt changes of the crystal structure were observed. The coordination sphere of the lithium ions is that of a distorted tetrahedron and remains almost unchanged, although the coordination number of the lithium ions decreases slightly with rising temperature, similarly to what was found for LiB3O5. An expected rigidity of the boron‐oxygen groups was confirmed. The thermal deformations of the [B4O7]2? framework occur according to the hinge mechanism. This indicates that the LiO4 chains change their winding on cooling, which leads to deformations along c.  相似文献   

13.
SUN  Hua-Yu ZHOU  Yan HUANG  Ya-Xi SUN  Wei MI  Jin-Xiao 《结构化学》2010,29(9):1387-1393
The hydroxy yttrium hexaborate,Y[B2O3(OH)]3,has been synthesized under mild hydrothermal conditions at 458 K.The crystal structure was solved and refined from single-crystal X-ray diffraction.It adopts a trigonal space group R3c(No.161) with a = 8.3942(4),c = 20.6484(12) ,V = 1260.03(12) 3,YB6H3O12,Mr = 348.79,Z = 6,Dc = 2.758 g/cm3,F(000) = 1008,μ = 7.015 mm-1,R = 0.0321 and wR = 0.0772.Its crystal structure is made up of six-membered rings,alternating three-connected [BO3(OH)] tetrahedra and planar [BO3] trigonal groups,which are interconnected with each other by sharing their common oxygen corners to form a three-dimensional framework structure with six-membered ring channels that are occupied by the yttrium atoms and run along the c axis.FT-IR,Raman,and TG-DTA results are also presented.  相似文献   

14.
标题化合物中,锌(Ⅱ)为四配位畸变的四面体构型。通过相邻分子之间的氢键把配合物连接成三维网络结构,而且,配合物中吡啶环与苯环之间存在着面-面的π–π相互作用。配体与配合物均可发出蓝色荧光,其固态时的最大发射峰为480 nm。  相似文献   

15.
Guanidimium‐4,4‐azo‐1‐hydro‐1,2,4‐triazol‐5‐one (GZTO·H2O) was synthesized from 4‐amino‐1,2,4‐triazol‐5‐one as a starting material by two‐step including oxidation coupling using acid KMnO4 and reaction with (NH2)2CNH·HNO3 (GN) in KOH solution. The single crystal of the title compound was obtained by slow evaporation method at room temperature, and its structure was firstly determined with X‐ray single‐crystal diffractometer. It is a orthorhombic crystal, space group Pbca with cell dimensions of a=1.0459(2) nm, b=1.3584(3) nm, c=1.6103(3) nm, α=90.00(10)°, β=90.00(11)°, γ=90.00(11)°, V=2.2878(8) nm3, Z=8, Dc=1.587 g·cm−3, F(000)=1136, µ=0.132 mm−1, R1=0.0455, wR2=0.1397. The thermal behavior of GZTO·H2O was studied under a non‐isothermal condition by DSC‐TGA method, and its thermal decomposition process can be divided into three stages, and the first stage is an intense exothermic decomposition process. The second stage and the third stage are slow exothermic decomposition processes. The critical temperature of thermal explosion is 237.74°C.  相似文献   

16.
Two uranyl sulfate hydrates, (H3O)2[(UO2)2(SO4)3(H2O)] · 7H2O (NDUS) and (H3O)2[(UO2)2(SO4)3(H2O)] · 4H2O (NDUS1), and one uranyl selenate‐selenite [C5H6N][(UO2)(SeO4)(HSeO3)] (NDUSe), were obtained and their crystal structures solved. NDUS and NDUSe result from reactions in highly acidic media in the presence of L ‐cystine at 373 K. NDUS crystallized in a closed vial at 278 K after 5 days and NDUSe in an open beaker at 278 K after 2 weeks. NDUS1 was synthesized from aqueous solution at room temperature over the course of a month. NDUS, NDUS1, and NDUSe crystallize in the monoclinic space group P21/n, a = 15.0249(4) Å,b = 9.9320(2) Å, c = 15.6518(4) Å, β = 112.778(1)°, V = 2153.52(9) Å3,Z = 4, the tetragonal space group P43212, a = 10.6111(2) Å,c = 31.644(1) Å, V = 3563.0(2) Å3, Z = 8, and in the monoclinic space group P21/n, a = 8.993(3) Å, b = 13.399(5) Å, c = 10.640(4) Å,β = 108.230(4)°, V = 1217.7(8) Å3, Z = 4, respectively.The structural units of NDUS and NDUS1 are two‐dimensional uranyl sulfate sheets with a U/S ratio of 2/3. The structural unit of NDUSe is a two‐dimensional uranyl selenate‐selenite sheets with a U/Se ratio of 1/2. In‐situ reaction of the L ‐cystine ligands gives two distinct products for the different acids used here. Where sulfuric acid is used, only H3O+ cations are located in the interlayer space, where they balance the charge of the sheets, whereas where selenic acid is used, interlayer C5H6N+ cations result from the cyclization of the carboxyl groups of L ‐cystine, balancing the charge of the sheets.  相似文献   

17.
A new gadolinium diphosphate [HGdP2O7 · 2 H2O] · NH3 was synthesized via a soft chemistry route from evaporation of aqueous solution. It crystallizes in the space group Pī with Z = 2 and the following unit cell dimensions: a = 6.4609(2), b = 6.9810(2), c = 9.813(4) ?, α = 81.345(3), β = 80.547(3), γ = 88.430(3)°. IR spectroscopy confirmed the presence of P-OH group, and both ammonia and water molecule in the studied material.

The thermal decomposition of [HGdP2O7 · 2 H2O] · NH3, as investigated by Controlled Rate Thermal Analysis, took place in three stages between -23 and 600 °C leading to the anhydrous salt HGdP2O7. The calcination of the synthesized product at 850 °C in a static air furnace allowed us to obtain the tetraphosphate Gd2P4O13. X-ray powder diffraction and infrared spectroscopy were used to identify these materials.

The electrical properties of HGdP2O7 and Gd2P4O13 were investigated through impedance complex analysis. Modest conductivity has been observed in both materials at relatively medium temperature range. Activation energies of 0.62 and 1.21 eV, were deduced from the Arrhenius plots for HGdP2O7 and Gd2P4O13, respectively.  相似文献   


18.
Ag2B4O7 is synthesized at high-pressure/high-temperature conditions of 11 GPa and 1073 K in a multianvil device. It crystallizes in the monoclinic centrosymmetric space group P21/c (no. 14) with four formula units per unit cell (Z=4). The cell parameters are a=787.53(3), b=651.63(2), c=943.88(3) pm, β=107.911(2)°, and V=460.90(3) Å3. Ag2B4O7 crystallizes in a unique crystal structure that consists of complex anionic borate layers with Ag+ ions in between. Additionally, the silver cations show argentophilic interactions. The compound was analysed via single-crystal and powder diffraction as well as infrared spectroscopy. Furthermore, theoretical calculations at HSEsol level were conducted.  相似文献   

19.
1INTRODUCTIONThecompoundwithcompositionIRE,O,:ZSiO,(RE~rareEarth)exhibitsex-tensivepolymorphismthatarecharacterizedbyboundariesateuropiumandholmiumalongtheseriesoftrivalentrareearths.Asfarasthestructureisconcerned,typeCisofspecialstabilitybecauseitsrangecanbeextendedbeyondthesmallestrareearthLug toScs tl'z}.Notlongago,wereportedstructureofNd,Si,O,withstructureformAt33.SynthesisandstructureofErZSiZO7withstructureformCarehereinre-ported.2EXPERIMENTAL'ThestartingmaterialsEr,O,…  相似文献   

20.
1 INTRODUCTION Halide fluxes are excellent media for growing single crystals of chalcogenides[1~5]. On our research in the Ln-Cu-Zn-Se system to find new phases and to search for potential infrared ceramic materials, two new compounds, KHo2CuSe4 and KEr2CuSe4, were synthesized from the reaction of the precursor with KCl flux[6]. In an attempt to synthesize the homologous sulfide by the same method using KBr as flux in a sealed evacuated quartz tube, single crystals of Ho4S3Si2O7 w…  相似文献   

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