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61.
使用一种新的高温固相反应方法合成得到了五个新的异质同构的四元稀土硫化物.它们结晶于六方晶系的手性空间群P63,属于ALn3EQ7(A:碱金属或货币金属 Ln:稀土元素 E:第IVA族元素 E:硫属元素)结构类型,晶胞参数为a=9.621(1)~10.038(2)A,c=5.672(2)~5.939(1)A,V=476.1(1)~494.9(2)A^3,Z=2.它们的晶体结构可以描述为:LnS8双帽三棱柱之间相互连接成三维框架结构,而A位和E位原子分别占据所形成的八面体和四面体空隙.化合物4的光学和磁性质的研究表明:它是光学带隙为2.34eV的半导体,并表现出类似于反铁磁相互作用的磁行为.  相似文献   
62.
The solution reactions of the metal salts with 2,2'-bipyfidine (2,2'-bipy) and ethyl tetrazole-5-carboxylate (Hetzc) afforded two new tetrazole-based complexes M(2,2'-bipy)2(etzc)2 (M=Mn 1, Zn 2), and their crystal structures were determined by single-crystal X-ray diffraction analyses. Crystallographic data for 1: C28H26MnN12O4, Mr = 649.55, monoclinic, space group C2/c, a= 19.326(15), b = 11.051(6), c = 16.388(13)А,β= 117.38(4)° V= 3108(4) А^3, Z= 4, Dc = 1.388 g/cm^3, F(000) = 1340, R = 0.0557 and wR = 0.1269; and those for 2: C28H26ZnN12O4, Mr = 659.98, monoclinic, space group C2/c, a = 19.173(4), b = 11.006(2), c = 16.266(4) А, β= 118.11(3)°, V= 3027.4(11) А^3, Z = 4, Dc=1.448 g/cm3, F(000) = 1360, R = 0.0428 and wR = 0.1000. The structures of 1 and 2 are isomorphic and consist of isolated neutral mononuclear units. The metal atoms have highly distorted octahedral coordination environments with two N atoms from two etzc ligands and four N atoms from two 2,2'-bipy molecules. The isolated mononuclear units are connected by π…π stacking interactions to generate one-dimensional chains. The thermal stability and photoluminescence have also been discussed.  相似文献   
63.
三核钼-硫配合物Mo_3S_7(dtc)_3I·S_8·2CH_2Cl_2(dtc=C_4H_8NCS_2~-)是由低热固相合成得到的。晶体属单斜晶系,M_r=1500.19,空间群P2_1/n,a=11.881(3),b=15.559(4),c=26.197(7),β=98.53(2)°,V=4789A~3,Z=4,D_c=2.08g/cm~3,F(000)=2920,μ(MoKα)=25.24cm~(-1),对于2397个I≥3σ(I)的独立衍射点,最终偏离因子R=0.060,R=0.066。该配合物的基本骨架是[Mo_3S_7(dtc)_3]~+,其簇芯为[Mo_3S_7]~(4+)单元,3中Mo原子组成正三角形平面,Mo-Mo的平均键长力2.723,Mo原子平面上的硫原子形成盖帽的μ_3-S,其Mo-S平均键长为2.383A,3个S_2基团分别位于三角形3个棱的外侧,并分别与邻近的两个Mo原子结合形成12中Mo-S键。与μ_3-S相对而位于平面另一侧的Ⅰ原子与3个μ_2-S连结,平均距离为3.257A,成键作用较弱。  相似文献   
64.
0IntroductionInthepastfewyears,themolecular-basedmag-neticpropertiesofheteronuclearcomplexessimultane-ouslycomprisinglanthanideandtransitionmetalionshaveattractedincreasinginterest犤1~6犦.Inourlaborato-ry,wehavesynthesizedsuchtypeofcomplexeswithdifferentcarboxylicbridgingligands犤7~10犦.Asanex-tensionofthisresearcharea,ourpresentworkaimstosynthesizenovelcomplexesofrareearthandtransi-tionmetalbyusingoroticacidasabridgingligand.Inthecourseofourinvestigationtwonewcomp-lexesof犤Cu(C5H2N2O4)(H…  相似文献   
65.
A new lanthanide complex [Sm(C2O4)(H2O)5]nCln·2nH2O has been obtained by hydrothermal synthetic method. The crystal belongs to monoclinic, space group P21/n, with a = 7.5438(6), b = 14.3201(11), c = 10.8608(9) , β = 94.565(4)o, V = 1169.55(16) 3, C2H14ClO11Sm, Mr = 399.93, Z = 4, Dc = 2.271 g/cm3, μ = 5.290 cm1, F(000) = 772, the final R = 0.0271 and wR = 0.0632 for 1880 observed reflections with I > 2σ(I). X-ray crystal analysis reveals that each Sm(III) atom is nine-coordinated by four oxygen atoms from two oxalate ligands and five coordinated water molecules in a distorted tricapped trigonal prism. The chain-like structure of lanthanide oxalate is reported for the first time. The fluorescent property and magnetic behavior of the title compound were investigated. The θ of –14.3(2)° and J of –0.26 cm-1 indicate antiferromagnetic interaction in the molecule.  相似文献   
66.
A new lanthanumⅢ-ironⅢ complex [La(DMSO)5(H2O)](μ-CN)2[Fe(CN)4]·H2O 1 (DMSO=dimethylsulfoxide) has been prepared by a facile approach,ball-milling method,and characterized by X-ray diffraction. The crystal belongs to monoclinic,space group P21/n with a= 9.7125(3),b=21.5336(7),c=14.3804(5),β=93.242(3)o,C16H34FeLaN6O7S5,Mr=777.55,V =3002.8(2)3,Z=4,Dc=1.720 g/cm3,S=1.053,μ(MoKα)=2.278 mm–1,F(000)=1564,R= 0.0490 and wR=0.1270. The crystal structure analysis of 1 reveals a slightly distorted square-antiprism eightfold-coordinated La(Ⅲ) ion and a 1-D zigzag chain structure extending through the Fe-CN-La-NC-Fe linkages. The [La(DMSO)5(H2O)](μ-CN)2[Fe(CN)4] species are held together via hydrogen bonds to form a three-dimensional framework.  相似文献   
67.
郭国聪  庄峻宁 《结构化学》1996,15(3):243-245
采用高温固相反应和化学气相传输法合成三硒化二饵,晶体属于四方晶系Mr=571.40,空间群为P4/nmm,a=3.984(1),c=8.228(3),A,V=130.59(7)A^3,Z=1,Dc=7.27g/cm^3,F(000)=238,μ(MoKa)=528.86cm^-1,对于187个I≥3σ(1)的独立衍射点,最后偏离因子R=0.066,Rw=0.078,化合物Er2Se3的晶体结构是由  相似文献   
68.
A dinuclear complex [DyFe(CN)6(DMF)4(H2O)3]·1.25H2O(DMF=N, N-dimethylformamide) 1 based on the cyanide as linkage was prepared and structurally characterized by X-ray single-crystal structure analysis. The Dy(Ⅲ) ion is eight coordinations in a square-antiprism arrangement and the Fe(Ⅲ) ion is six coordinations oriented octahedrally. The neutral units [DyFe(CN)6(DMF)4(H2O)3] are held together by hydrogen bonds formed by lattice water molecules, coordinated water molecules and nitrogen atoms of cyanide coming from other distinct complex units to afford a three-dimensional framework. CCDC: 192314.  相似文献   
69.
Under hydrothermal conditions the reaction of cis-aconitic acid with Cu2(OH)2CO3 and bipy (bipy = 2,2'-bipy) in H2O/DMF (3:2) afforded a neutral mononuclear compound [Cu- (bipy)((2-CO3)(H2O)](2H2O, which has been structurally characterized by single-crystal X-ray diffraction analysis. The crystal belongs to triclinic, space group Pī with a = 8.3950(5), b = 8.7974(5), c = 9.4496(3)(A。), α = 98.270(3), β = 93.014(3), γ = 100.068(3)°, V = 677.83(6) (A。)3, Dc = 1.635 g/cm3, Z = 2, C11H14CuN2O6, Mr = 333.78, μ = 1.637 mm-1, λ(MoKα) = 0.71073 (A。), F(000) = 342, the final R = 0.0616 and wR = 0.1273 for 1621 observed reflections with I > 2σ(I). The structure of the complex contains a distorted square pyramidal core with a bipy, a carbonate anion and a water molecule coordinating to a CuⅡ atom. The dihedral angle between the two planes composed of N(1)N(2)Cu(1) and O(1)O(3)Cu(1) is 21.73(8)°. The intermolecular hydrogen bonds (O…O) are observed in the crystal structure.  相似文献   
70.
王庆华  郭国聪 《结构化学》2001,20(6):481-485
1 INTRDUCTION Supramolecular chemistry of coordination compounds is the subject of intense research in recent years[1a]. Besides covalent bond, some weaker intermolecular interactions such as S…S con- tacts[1b], weak coordination, hydrogen bonding and pp stacking[1c] are efficient organising forces in supramolecular architecture. The properties of solid state materials may be quite different from those of isolated molecule due to the intermolecular interaction. In previous work[1d], we …  相似文献   
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