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Synthesis,Crystal Structure and Optical and Photocatalytic Properties of a Discrete Cuprous Iodide Compound with a Transition Metal Complex Cation 被引量:2
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作者 张波 张杰 +2 位作者 冯美玲 叶晓云 黄小荥 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第1期25-32,共8页
With transition metal complex, a discrete cuprous iodide compound, namely, [Ni(phen)3]2Cu6I10(1, phen = 1,10-phenanthroline) has been solvothermally synthesized and structurally characterized. Single-crystal X-ray... With transition metal complex, a discrete cuprous iodide compound, namely, [Ni(phen)3]2Cu6I10(1, phen = 1,10-phenanthroline) has been solvothermally synthesized and structurally characterized. Single-crystal X-ray diffraction studies revealed that compound 1 crystallizes in triclinic space group P1(No. 2) with a = 11.2694(2), b = 12.3699(3), c = 15.0387(3) ?, α = 102.840(2), β = 105.215(2), γ = 96.388(2)°, V = 1940.04(7) ^3, Z = 1, Dc = 2.438 g·cm^-3, F(000) = 1324, R = 0.0256 and w R = 0.0555(I 〉 2σ(I)). Compound 1 features a discrete anionic moiety of [Cu6I10]^4- charge-balanced by two metal complexes of [Ni(phen)3]2+. The optical absorption edge of compound 1 was estimated to be 2.24 eV. Interestingly, nearly 95% of contaminant(crystal violet aqueous solution(CV), 50 m L, 1.0 × 10^-5 M) could be decolorized after exposure to visible light within 30 min, illustrating an impressive photocatalytic activity of compound 1. The thermal stability of 1 has also been studied. 展开更多
关键词 cuprous iodide transition metal complex crystal structure photocatalysis
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Preparation and Crystal Structure of Hetero-metal Clusters [η~5-C_5H_4C(O)CH_2CH_2C(O)OCH_3]FeCoM(μ_3-S)(CO)_8 (M = Mo or W)
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作者 张玉华 袁建超 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第5期363-368,共6页
The hetero-metal clusters [■5-C5H4C(O)CH2CH2C(O)OCH3]FeCoM(■3-S)(CO)8 (M = Mo 1, M = W 2) were prepared by thermal reactions of FeCo2(CO)9((3-S) with metal exchange reagent [■5-C5H4C(O)CH2CH2C(O)O... The hetero-metal clusters [■5-C5H4C(O)CH2CH2C(O)OCH3]FeCoM(■3-S)(CO)8 (M = Mo 1, M = W 2) were prepared by thermal reactions of FeCo2(CO)9((3-S) with metal exchange reagent [■5-C5H4C(O)CH2CH2C(O)OCH3]M(CO)3Na (M = Mo or W) in THF. Cluster 1 reacted with 2,4-dinitrophenylhydrazine at room temperature to yield the cluster hydrazone derivative ((3-S)CoFeMo(CO)8[(5-C5H4C(NR)Me] [R = NHC6H3-2,4-(NO2)2] 3. All the compounds were characterized by elemental analyses, IR and NMR spectra. Cluster 1 was determined by single crystal X-ray diffraction. Crystal data: C18H11O11SCoFeMo, Mr = 646.05, triclinic, space group P, a = 8.148(2), b = 10.685(3), c = 13.410(4) ?, ( = 100.077(5), ( = 102.452(5), ( = 91.108(6)(, V = 1120.4(5) ?3, Z = 2, Dc = 1.915 g/cm3, F(000) = 636, ( = 2.071 mm(1, the final R = 0.0378 and wR = 0.0968 for 5074 observations with (I > 2((I)). 展开更多
关键词 transition metal cluster complex chiral crystal structure
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Syntheses of Two Chiral Clusters [η~5-C_5H_4C(NR)CH_3]- RuNiM(CO)_5(μ_3-S) (R =NH-C_6H_3-2,4-(NO_2)_2,M=Mo,3;M=W,4) and the Single-crystal Structure of Cluster 3
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作者 边治国 陈玉岗 +1 位作者 殷元骐 李庆山 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第3期301-304,共4页
The new chiral clusters [h5-C5H4C(NR)CH3]RuNiM(CO)5(m3-S) (R = NH-C6H3-2,4- (NO2)2, M = Mo, 3; M = W, 4) were synthesized and the structure of cluster 3 was determined by single-crystal X-ray analysis. Crystal data: C... The new chiral clusters [h5-C5H4C(NR)CH3]RuNiM(CO)5(m3-S) (R = NH-C6H3-2,4- (NO2)2, M = Mo, 3; M = W, 4) were synthesized and the structure of cluster 3 was determined by single-crystal X-ray analysis. Crystal data: C23H16O9N4MoNiRuS, Mr = 780.18, orthorhombic, space group Pbca with the following crystallographic parameters: a = 13.207(4), b = 16.036(5), c = 25.513(8) , Z = 8, V = 5403(3) 3, Dc = 1.918 g/cm3, m = 1.834 mm-1 and F(000) = 3072. The final R = 0.0512 and wR = 0.1132 for 2525 reflections with I > 2.00s(I). 展开更多
关键词 synthesis chiral cluster crystal structure
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Synthesis and Crystal Structure of Novel Mixed-metal Alkoxide Clusters of Ytterbium and Sodium: Yb_4O_4(O^iPr)_(16)Na_(12)
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作者 王辉 盛鸿婷 +5 位作者 冯燕 史建华 何森 盛含晶 张勇 沈琪 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第4期571-577,共7页
The mixed-metal cluster Yb4O4(OiPr)16Na12 has been synthesized and structurally determined by IR, elemental analysis, and single-crystal X-ray diffraction. The crystal belongs to the cubic system, space group P23 wi... The mixed-metal cluster Yb4O4(OiPr)16Na12 has been synthesized and structurally determined by IR, elemental analysis, and single-crystal X-ray diffraction. The crystal belongs to the cubic system, space group P23 with a = b = c = 13.9788(3)A, V = 2731.55(10)A3, Z = 1, Dc = 1.202 g/cm3, Mr = 1977.42,/J = 3.480 mm-1, F(000) = 972, the final R = 0.0288 and wR = 0.1511 for 1677 observed reflections with I 〉 2σ(I). X-ray analysis reveals that Yb4O4(Oipr)16Na12 is centrosym- metric and the structure contains four ytterbium metals and twelve sodium metals, and each ytterbium atom is coordinated by six oxygen atoms. In addition, an ancillary computational analysis of the optimized molecular unit was provided. The large energy gap (3,31 eV) between HOMO and LUMO indicates that the structure framework is particularly stable. 展开更多
关键词 mixed-metal cluster YTTERBIUM ALKOXIDE crystal structure computational analysis
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Synthesis and Structures of A Series of Novel Rare Earth Transition Metal Sulfates 被引量:1
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作者 王希渠 刘鲁美 Allan J.Jacobson 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第6期659-662,共4页
Seven new rare earth transition metal sulfates were synthesized by hydrothermal reactions under conditions slightly above the critical point of water. Their crystal structures were determined from single crystal X-ray... Seven new rare earth transition metal sulfates were synthesized by hydrothermal reactions under conditions slightly above the critical point of water. Their crystal structures were determined from single crystal X-ray data. The compositions of the new compounds can be represented by two general formulae : REM (OH) 3 (SO4) and RE2M (OH) 3 (SO4) 2F (H2O) with RE = Gd, Tb, Dy ; M = Ni, Cu. Three different crystal structure types were found for the formula REM (OH) 3 (SO4). The structures of the new compounds all feature infinite chains of REOn coordination polyhedra, which are connected to chains of CuO6 or NiO6 octabedra. The limited size range of the rare earth cations observed in these compounds is most likely because of interactions between the octabedral chains and the chains of REOn polyhedra. The new compounds are closely related to the known yttrium transition metal sulfates. 展开更多
关键词 rare earth sulfate transition metal sulfate hydrothermal synthesis crystal structure
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Hydrothermal Synthesis and Crystal Structure of a Highly Reduced Mixed Molybdenum-vanadium Polyoxometalate with Phosphorus-centered [Ni(phen)_3]_2H_2· [PMo_4~ⅤMo_4~ⅥV_6~ⅣM_2M_(44)]^(5-)·4H_2O(M=0.78Mo~Ⅴ+0.22V~Ⅳ)
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作者 SUNYing-hua DINGHong +2 位作者 XUJi-qing LIYong LIGuang-hua 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第3期368-371,共4页
关键词 Hydrothermal synthesis POLYOXOmetalATE crystal structure transition metal
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Hydrothermal Syntheses and Crystal Structures of Six Complexes Constructed from 1,3,5-Benzenetricarboxylic Acid and 4'-(4-Pyridyl)-2,2':6',2''-terpyridine Mixed Ligands 被引量:4
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作者 乔宇 王炫博 +4 位作者 周艳凤 刘力辉 车广波 刘春波 刘晓腾 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第8期1381-1394,共14页
Six new transition metal complexes, [Zn(HBTC)(PYTPY)]n·n PYTPY(1), [Cu(HBTC)(PYTPY)]n·n PYTPY(2), [Co(HBTC)(PYTPY)]n·n DMF(3), [Mn(HBTC)(PYTPY)]n·n DMF(4), [Cd(HBTC)(PYTP... Six new transition metal complexes, [Zn(HBTC)(PYTPY)]n·n PYTPY(1), [Cu(HBTC)(PYTPY)]n·n PYTPY(2), [Co(HBTC)(PYTPY)]n·n DMF(3), [Mn(HBTC)(PYTPY)]n·n DMF(4), [Cd(HBTC)(PYTPY)(H2O)]n·2nH2O(5), and [Co(HBTC)(PYTPY)(H2O)2](6),(H3BTC = 1,3,5-benzenetricarboxylic acid, PYTPY = 4'-(4-pyridyl)-2,2':6',2''-terpyridine, DMF = N,N?-dimethylformamide), have been synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. Complexes 1~5 all feature one-dimensional chain structures, and complex 6 exhibits a zero-dimensional structure. Complexes 1~5 present three-dimensional(3D) supramolecular frameworks via π-π stacking interactions, whenas 6 has also a 3D supramolecular structure assembled by hydrogen bonding. Meanwhile, complexes 1 ~ 6 exhibit the thermal stabilities and photoluminescent properties. 展开更多
关键词 transition metal complex 1 3 5-benzenetricarboxylic acid 4'-(4-pyridyl)-2 2' 6' 2''-terpyridine crystal structure
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Synthesis and Structural Chemistry of Two Novel Transition Metal Organic Phosphonates 被引量:1
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作者 胡进 张汉辉 +4 位作者 曹彦宁 张春刚 张帅 陈义平 孙瑞卿 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第8期939-946,共8页
Two novel transition metal phosphonate compounds, [Co(H2BDPP)(phen)]n 1 (BDPP = p-O3PCH2(C6H4)CH2PO3, phen = 1,10-phenanthroline) and [Pb3(BCP)2]n 2 (BCP = OOC(C6H4)CH2PO3), have been synthesized and str... Two novel transition metal phosphonate compounds, [Co(H2BDPP)(phen)]n 1 (BDPP = p-O3PCH2(C6H4)CH2PO3, phen = 1,10-phenanthroline) and [Pb3(BCP)2]n 2 (BCP = OOC(C6H4)CH2PO3), have been synthesized and structurally determined by X-ray single-crystal diffraction. Compound 1 crystallizes in the monoclinic system, space group C2/c with a = 21.169(4), b = 12.001(2), c = 7.6211(15)A, β = 98.03(3)°, V= 1917.2(6)A^3, C20H18N2O6P2Co, Mr = 505.22, Z = 8, De= 1.737 g/cm^3, p = 1.107 mm^-1, F(000) = 1020, the final R= 0.0450 and wR = 0.1306 for 2072 observed reflections (I 〉 2σ(I). Compound 2 crystallizes in the monoclinic system, space group C2/c with a = 4.7167(9), b = 18.753(2), c = 22.781(3)A, β = 91.07(3)°, V= 2014.7(14)A^, C8H6O5PPb1.5, Mr = 523.88, Z = 8, Dc = 3.454 g/cm^3, p = 25.222 mm^-1, F(000) = 1856, the final R = 0.0441 and wR = 0.1906 for 2259 observed reflections (I 〉 2σ(I). In compound 1, the 1D chain running along the c axis is bridged by four ligands (trans- HO3PCH2C6H4CH2PO3H) in four different directions to extend the structure into a three- dimensional network. In compound 2, the Pb(II) displays 4- and 5-coordination modes. There is a one-dimensional P-O-Pb band along the a axis formed by PO3 groups and Pb(II) cations. These bands are joined by μ2-O of -COO to yield two-dimensional inorganic P-O-Pb layers which are pillared by the OOCC6HaCH2PO3 ligands to form a three-dimensional network. Moreover, compound 2 displays a strong emission band attributed to the ligand-centered (LC) transition. 展开更多
关键词 transition metal organic phosphonate hydrothermal synthesis crystal structure
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Pressure-induced phase transition in transition metal trifluorides
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作者 Peng Liu Meiling Xu +6 位作者 Jian Lv Pengyue Gao Chengxi Huang Yinwei Li Jianyun Wang Yanchao Wang Mi Zhou 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第10期102-106,共5页
As a fundamental thermodynamic variable, pressure can alter the bonding patterns and drive phase transitions leading to the creation of new high-pressure phases with exotic properties that are inaccessible at ambient ... As a fundamental thermodynamic variable, pressure can alter the bonding patterns and drive phase transitions leading to the creation of new high-pressure phases with exotic properties that are inaccessible at ambient pressure. Using the swarm intelligence structural prediction method, the phase transition of TiF_(3), from R-3c to the Pnma phase, was predicted at high pressure, accompanied by the destruction of TiF_6 octahedra and formation of TiF_8 square antiprismatic units. The Pnma phase of TiF_(3), formed using the laser-heated diamond-anvil-cell technique was confirmed via high-pressure x-ray diffraction experiments. Furthermore, the in situ electrical measurements indicate that the newly found Pnma phase has a semiconducting character, which is also consistent with the electronic band structure calculations. Finally, it was shown that this pressure-induced phase transition is a general phenomenon in ScF_(3), VF_(3), CrF_(3), and MnF_(3), offering valuable insights into the high-pressure phases of transition metal trifluorides. 展开更多
关键词 high-pressure structure transition crystal structure prediction high-pressure x-ray diffraction experiments transition metal
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Progress in functional studies of transition metal borides
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作者 Teng Ma Pinwen Zhu Xiaohui Yu 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第10期98-107,共10页
In recent years,transition metal borides(TMBs)have attracted much attention because they are considered as potential superhard materials and have more abundant crystal structures compared with traditional superhard ma... In recent years,transition metal borides(TMBs)have attracted much attention because they are considered as potential superhard materials and have more abundant crystal structures compared with traditional superhard materials.So far,however,no superhard materials have been found in TMBs.A large number of structures and potential new properties in TMBs are induced by the various hybridization ways of boron atoms and the high valence electrons of transition metals,which provide many possibilities for its application.And most TMBs have layered structures,which make TMBs have the potential to be a two-dimensional(2D)material.The 2D materials have novel properties,but the research on 2D TMBs is still nearly blank.In this paper,the research progress of TMBs is summarized involving structure,mechanical properties,and multifunctional properties.The strong covalent bonds of boron atoms in TMBs can form one-dimensional,twodimensional,and three-dimensional substructures,and the multiple electron transfer between transition metal and boron leads to a variety of chemical bonds in TMBs,which are the keys to obtain high hardness and multifunctional properties of TMBs.Further research on the multifunctional properties of TMBs,such as superconductors,catalysts,and high hardness ferromagnetic materials,is of great significance to the discovery of new multifunctional hard materials. 展开更多
关键词 transition metal borides crystal structure HARDNESS multifunctional properties
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Synthesis and Crystal Structure of (CO) 5ReSnMe 2Re(CO) 5
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作者 Li, J Liu, H +2 位作者 Song, XQ Kai, L Yin, N 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1999年第2期39-43,共5页
The crystal structure of the title complex (CO) 5ReSnMe 2Re(CO) 5, (C 12 H 6O 10 Re 2Sn, M r =801.27), has been determined by single crystal X ray diffraction. The crystal is monoclinic with space g... The crystal structure of the title complex (CO) 5ReSnMe 2Re(CO) 5, (C 12 H 6O 10 Re 2Sn, M r =801.27), has been determined by single crystal X ray diffraction. The crystal is monoclinic with space group P2 1/n (NO.14), a=10.587(2), b=12.392(2), c = 14.594(3) , β = 100.59(3)°, V = 1882(1) 3, D x = 2.828 g·cm -3 , F(000)=1432, μ =14.3759mm -1 , Z =4, and final R =0 0440 and R w =0 0483 for 1954 reflections ( I≥3σ(I )). In the complex the Sn atom is connected to two methyl groups and two Re atoms which are in slightly distorted tetrahedral arrangement. The Re atom is coordinated by five carbonyl ligands and one Sn atom, forming an octahedral structure. 展开更多
关键词 metal CARBONYL cluster Re COMPLEX synthesis crystal structure
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Solvothermal Synthesis and Crystal Structure of Zn(en)_3B_5O_7(OH)_3
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作者 HE Yi CHEN Wei YANG Jin XI Chun-yu CHEN Jie-sheng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第3期271-273,共3页
A new polyborate containing ehiral metal-complex Zn(en)3 B5O7(OH)3, where en = ethylenediamine, was synthesizedunder solvothermal conditions and structurally characterized by means of X-ray diffraction analysis. C... A new polyborate containing ehiral metal-complex Zn(en)3 B5O7(OH)3, where en = ethylenediamine, was synthesizedunder solvothermal conditions and structurally characterized by means of X-ray diffraction analysis. Crystal data: Zn(en)3 B5O7(OH)3, monoclinic, space group P21/c, a =0.8532(72) nm, b =2.3340(5) nm, c = 0.9526(92) nm, β =107. 04(3)°, Z=4, V=1.8140(6) nm^3, Dc =1.694 g/cm^3, p=1.416 mm^-1, F(000) = 960, GOF = 1. 020, R =0. 0276, Rw =0. 0828. There is a chiral Zn(en)3^2+ complex cation and an isolated B5O7(OH)3^2- group in a Zn(en)3 B5O7(OH)3 molecule. The enantiomer of the chiral complex cation is separated orderly as ,4 and A configurations in the compound and the borate group consists of two B303 cycles linked through a bridging boron atom. 展开更多
关键词 Solvothermal synthesis crystal structure chiral metal-complex Borate compound
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A New Heterometallic 3d-3d Transition Metal Oxo-cluster{Cu^(Ⅱ)_(6)Mn^(Ⅲ)}:Synthesis,Crystal Structure and Magnetic Property
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作者 WANG Yi-Man PENG Zhi-Wei +7 位作者 LIAO Jia-Min LI Ao LIU Yuan-Yan ZHANG Jing-Jing ZHOU Nian LI Xu-Dong LI Shu MENG Wei 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2021年第12期1661-1667,1554,共8页
A new transition metal-antimony oxo-cluster based compound has been synthesized in water under room temperature.Its formula is Na_(6)[Cu_(6)MnSb_(6)(μ_(3)-OH)_(2)(OH)(μ_(4)-O)_(6)(tartrate)_(6)]-_(2)0H_(2)O(1),where... A new transition metal-antimony oxo-cluster based compound has been synthesized in water under room temperature.Its formula is Na_(6)[Cu_(6)MnSb_(6)(μ_(3)-OH)_(2)(OH)(μ_(4)-O)_(6)(tartrate)_(6)]-_(2)0H_(2)O(1),where tartrate represents rac-tartaric acid.It was characterized by elemental analysis,infrared spectrum and X-ray single-crystal diffraction.The compound crystallizes in the monoclinic system,space group P2_(1/n).Structural analyses revealed that two Sb_(3)(μ_(3)-0)(tartrate)_(3)scaffolds sandwich a Cu^(Ⅱ)_(_(6))Mn^(Ⅲ)middle layer to form the cluster.In the middle layer,all the seven metal ions lie in an almost regular hexagon,with Mn^(Ⅲ)ion in the center and six Cu^(Ⅱ)ions along the edges of the hexagon.As a 4-connected node,each cluster is interlinked to its nearest four{Cu_(6)Mn}neighbors through Na^(+),generating a 3D supramolecular framework.The temperature-dependent magnetic susceptibilities indicated dominating antiferromagnetic interactions in 1 with J_(Cu-Cu)=176.34 and J(Cu-Mn)=-14.44 cm^(-1). 展开更多
关键词 dipotassium bis(μ-tartrato)-diantimony(Ⅲ)ligand heterometallic transition metal oxo-cluster crystal structure magnetic study
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METAL CLUSTERS SYNTHESIZED BY SOLID STATE REACTION——PREPARATION AND CRYSTAL STRUCTURE OF TWO MIXED METAL CLUSTERS,Ni_2Nb_2Te_4(Ⅰ) AND Ni_2Ta-2Te_4(Ⅱ)
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作者 黄金陵 刘世雄 黄宝泉 《Science China Chemistry》 SCIE EI CAS 1991年第6期666-674,共9页
The two title compounds obtained by solid state reaction at high temperature were char-acierized as isomorphism by single--crystal X--ray diffraction. The space group of both crys-tals is C_(2v)~4-Pma2, with lattice c... The two title compounds obtained by solid state reaction at high temperature were char-acierized as isomorphism by single--crystal X--ray diffraction. The space group of both crys-tals is C_(2v)~4-Pma2, with lattice constants a = 7.955(1), b=6.258 (1), c=7 .203(2)A forI, and a =7.914 (1), b=6.237 (1), c=7.236 (1) ? for Ⅱ, Z=2. The structures were de-termined by normal method and refined to the final R = 0.074 and 0.083, respectively. Theresults show that the structure may be regarded as building by cluster unit with formulaNi_2M_2Te_4 (M =Nb or Ta) in which two Ni atoms and two M atoms form a rhombus, whilethe Te atoms are distorted tetrahedrally coordinated with both kinds of metal atoms. In thecluster unit there exist interactions between Ni atoms as well as between Ni and M atoms.In addition, all the cluster units are linked together not only by bridging Te atoms, but alsoby weaker metal-metal interactions, so as to form two--dimensional network. Therefore, thestructure may be represented by the formula [Ni_2M_2(μ_4--Te)_(6/3) (μ_4--Te)_(4/2) ]_∞. A preliminarymeasurement of electric conductivity shows that the crystals of the two title compounds aremetallic but their conductivities are anisotropic; those parallel to the a-b axes are about10~3Ω^(-1)·cm^(-1), whereas those along the c axis are about 10Ω^(-1)·cm^(-1). 展开更多
关键词 metal clusterS crystal structure solid state CHEMISTRY TELLURIDES
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Pressure-induced phase transition and electronic structure evolution in layered semimetal HfTe_(2)
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作者 张美光 陈磊 +4 位作者 冯龙 拓换换 张云 魏群 李培芳 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第8期349-354,共6页
Motivated by the recent experimental work,the pressure-induced structural transition of well-known two-dimensional(2D)1T-Hf Te_(2)was investigated up to 50 GPa through the advanced CALYPSO structure search technique c... Motivated by the recent experimental work,the pressure-induced structural transition of well-known two-dimensional(2D)1T-Hf Te_(2)was investigated up to 50 GPa through the advanced CALYPSO structure search technique combined with the first-principles calculations.Our calculations suggested that the 1T-Hf Te_(2)will first transform to C2/m phase at 3.6 GPa with a volume reduction of 7.6%and then to P62m phase at 9.6 GPa with a volume collapse of 4.6%.The occurrences of 3D C2/m and P62m phases mainly originated from the enhanced Te-Te interlayer coupling and the drastic distortions of Hf-Te polyhedrons in P3m1 phase under compression.Concomitantly,the coordination number of Hf atoms increased from six in P3m1 to eight in C2/m and eventually to nine in P62m at elevated pressure.The metallic and semimetallic nature of C2/m and P62m phases were characterized,and the evidence of the reinforced covalent interactions of Te-Hf and Te-Te orbitals in these two novel high-pressure phases were manifested by the atom-projected electronic DOS and Bader charge. 展开更多
关键词 transition metal dichalcogenides pressure-induced phase transition crystal structure electronic structure
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Syntheses,Crystal Structures and Fluorescence Properties of Two Complexes Based on a New Chiral Ligand 被引量:4
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作者 周霞丽 舒谋海 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第9期1518-1525,共8页
A new homochiral ligand,(R)-2-(4-pyridyl)-4,5-dihydrothiazole-4-carboxylic acid(HL^R), has been synthesized. Two complexes, [ZnL2^R(H2O)2]·H2O(1) and [MnL2^R(H2O)2]?H2O(2) have been prepared by the... A new homochiral ligand,(R)-2-(4-pyridyl)-4,5-dihydrothiazole-4-carboxylic acid(HL^R), has been synthesized. Two complexes, [ZnL2^R(H2O)2]·H2O(1) and [MnL2^R(H2O)2]?H2O(2) have been prepared by the reactions of Zn(Ⅱ) and Mn(Ⅱ) ions with the ligand HLR, and characterized by single-crystal X-ray diffraction analysis and fluorescence. Complexes 1 and 2 are isomorphs, and both of the Zn(Ⅱ) and Mn(Ⅱ) centers in 1 and 2 are six-coordinated by the two NO units of two ligands and two water oxygen atoms, showing distorted octahedral coordination geometry. Complexes 1 and 2 show fluorescent properties in the solid state at room temperature. 展开更多
关键词 transitional metal complexes synthesis crystal structure FLUORESCENCE
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Local electronic structure and magnetic properties of 3d transition metal doped GaAs 被引量:1
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作者 LIN He1 & DUAN HaiMing21 Department of Chemistry,Institute of Applied Chemistry,Xinjiang University,Urumqi 830046,China 2Department of Physics,Xinjiang University,Urumqi 830046,China 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2008年第5期470-480,共11页
The local electronic structure and magnetic properties of GaAs doped with 3d transition metal (Sc, Ti, V, Cr, Mn, Fe, Co, Ni) were studied by using discrete variational method (DVM) based on density functional theory.... The local electronic structure and magnetic properties of GaAs doped with 3d transition metal (Sc, Ti, V, Cr, Mn, Fe, Co, Ni) were studied by using discrete variational method (DVM) based on density functional theory. The calculated result indicated that the magnetic moment of transition metal increases first and then decreases, and reaches the maximum value when Mn is doped into GaAs. In the case of Mn concentration of 1.4%, the magnetic moment of Mn is in good agreement with the experimental result. The coupling between impure atoms in the system with two impure atoms was found to have obvious variation. For different transition metal, the coupling between the impure atom and the nearest neighbor As also has different variation. 展开更多
关键词 DILUTED MAGNETIC SEMICONDUCTOR density functional theory 3d transition metal cluster model electronic structure
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Synthesis and crystal structure of trinuclear Fecarbonyl cluster Fe_3(CO)_8S_2CNC_6H_5
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作者 徐吉春 焦凤英 +2 位作者 殷元棋 黄幼青 胡盛志 《Chinese Science Bulletin》 SCIE EI CAS 1995年第2期124-127,共4页
Metal cluster chemistry is an active studying field nowadays. It is possible that metal clusters can be developed as new homogeneous catalysts with special functions. Organoiron clusters, which could be easily synthes... Metal cluster chemistry is an active studying field nowadays. It is possible that metal clusters can be developed as new homogeneous catalysts with special functions. Organoiron clusters, which could be easily synthesized at lower price, are very important in metal cluster chemistry. Fe<sub>3</sub>(CO)<sub>12</sub> is a very useful compound with higher activity than Fe(CO)<sub>5</sub> in 展开更多
关键词 TRINUCLEAR IRON cluster transition metal COMPOUND crystal structure.
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Synthesis and Structure of Propionate-bridged Mixed-metal Cluster Compound:〔MoW2O2(O2CC2H56(H2O)3〕ZnBr4·4H2O
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《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1994年第1期52-55,共页
The heterotrinuclear cluster compound [MoW<sub>2</sub>O<sub>2</sub> (O<sub>2</sub>CC<sub>2</sub>H<sub>5</sub> )<sub>6</sub>-( H<sub>2<... The heterotrinuclear cluster compound [MoW<sub>2</sub>O<sub>2</sub> (O<sub>2</sub>CC<sub>2</sub>H<sub>5</sub> )<sub>6</sub>-( H<sub>2</sub>O)<sub>3</sub>] ZnBr4·4H<sub>2</sub>O was prepared by the redox reaction of Mo (CO)<sub>6</sub> with Na<sub>2</sub>W<sub>O</sub>4 in propionic anhydride. The crystal is monoclinic of space group P2/c with a =16. 334(4) , b= 9. 657(5) , c=19. 889(9) ,β= 139. 79 (5)°,V= 2026 (2)  ̄3 , Z=2 , D<sub>c</sub>=2. 30 g/cm ̄3 μ(MoKa) =106. 6 cm ̄(-1) ,F(000)=1176 ,final R=0. 065 and R<sub>ω</sub>=0. 072 for 1964 reflections with I≥3σ(I). In the structure of cation [MoW<sub>2</sub>O<sub>2</sub> (O<sub>2</sub>CC<sub>2</sub>H<sub>5</sub> )<sub>6</sub> (H<sub>2</sub>O)<sub>3</sub>] ̄(2+) molybdenum and tungsten atoms are statistically disordered. Three metal atoms form an equilateral triangle with the distance of M-M being 2. 735. 展开更多
关键词 SYNTHESIS crystal structure mixed-metal cluster Mo-W propionate compound
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A novel superhard tungsten nitride predicted by machine-learning accelerated crystal structure search 被引量:17
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作者 Kang Xia Hao Gao +4 位作者 Cong Liu Jianan Yuan Jian Sun Hui-Tian Wang Dingyu Xing 《Science Bulletin》 SCIE EI CSCD 2018年第13期817-824,共8页
Transition metal nitrides have been suggested to have both high hardness and good thermal stability with large potential application value, but so far stable superhard transition metal nitrides have not been synthesiz... Transition metal nitrides have been suggested to have both high hardness and good thermal stability with large potential application value, but so far stable superhard transition metal nitrides have not been synthesized. Here, with our newly developed machine-learning accelerated crystal structure searching method, we designed a superhard tungsten nitride, h-WN6, which can be synthesized at pressure around 65 GPa and quenchable to ambient pressure. This h-WN6 is constructed with single-bonded armchair-like N6 rings and presents ionic-like features, which can be formulated as W^2.4+N^2.4-. It has a band gap of 1.6 eV at 0GPa and exhibits an abnormal gap broadening behavior under pressure. Excitingly, this h-WN6 is found to be the hardest among transition metal nitrides known so far (Vickers hardness around 57 GPa) and also has a very high melting temperature (around 1,900 K). Additionally, the good gravimet- ric (3.1 kJ/g/and volumetric (28.0 kJ/cm3) energy densities make this nitrogen-rich compound a potential high-energy-density material, These predictions support the designing rules and may stimulate future experiments to synthesize superhard and high-energy-density material. 展开更多
关键词 Tungsten nitride transition metal nitrides Machine-learning accelerated crystal structure searching method Superhard tungsten nitride
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