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51.
用FTIR, NIR FT-Raman, UV-Vis DRS和荧光光谱等对五个新型具有[(PO4)4MoⅤ6O15]12-阴离子簇的化合物: Na·(H4TETA)3·(H3O)5·{Zn[(HPO4)2(PO4)2Mo6O15]2} (2), (H2 en)7·(H3O)4·{Cu[(HPO4)2(PO4)2Mo6O15]2}·H2O (3), (H3DETA)2·(H3O)3·{Co0.5[(HPO4)2(PO4)2Mo6O15]}·H2O (4), [Co(H3TETA)]2{Co0.5[(HPO4)(PO4)3Mo6O15]}·3.5H2O (5)和(H3DETA)·(H3O)4·{Co1.5[(HPO4)2(PO4)2Mo6O15]}·0.5H2O (6), 进行研究, 并探讨其结构和性能的关系. 这些化合物具有{M[(PO4)4Mo6 O15]2}二聚体单元, 化合物2~4的二聚体间通过与有机分子和水分子的氢键形成三维网状结构; 化合物5和6的{Co[(PO4)4Mo6O15]2}二聚体间是分别通过 [CoH3TEATA]基团和CoO4四面体组成网状结构. 磷钼酸盐的特征振动频率和这些化合物的结构相关; 化合物的三个UV-Vis DRS特征谱带分别属于Od→Mo, Oμ→Mo 和O→M电荷转移; 观察到以240 nm激发, 在410 nm附近出现的由Oμ→Mo跃迁激发引起的较强的荧光发射谱带.  相似文献   
52.
1 INTRODUCTION Recently, functional models for oxo-bridged diiron (Ⅲ) complexes have received much attention[1, 2]. They provide structural models for diiron sites in several proteins involved in oxygen storage of hemerythrin[3] and oxygen activation of methane monooxygenase[4]. In addition, several synthetic FeOFe (-oxo) diiron(Ⅲ) complexes show catalase-like activity[5, 6]. One of our studies in this respect is trying to synthesis -oxo bridged diiron complexes. The compound [Fe(ph…  相似文献   
53.
在水热的条件下合成了1个标题的Mo-Ni-O异核簇合物,化学式为H34Ni5Mo12O52 (Mr = 2311.10),用单晶X射线衍射方法测定了它的结构,该晶体属四方晶系,I41/amd空间群,晶胞参数为a = 15.319(2),c = 30.645(3) ,V = 7191.2(16) 3,Z = 4,Dc = 2.135 g/cm3,μ= 3.369 mm-1, F(000) = 4376, 1036个可观察衍射点(I > 2s(I)),最终结构偏离因子R = 0.0560,wR = 0.1632,S = 1.002。该化合物簇阴离子笼中心是Ni2+,由12个MoO6八面体和4个NiO6八面体通过共角和共边构成。  相似文献   
54.
The title compound (C6N3H18)2Ti4O4(C2O4)7(4H2O 1 (C13H22N3O18Ti2, Mr = 604.14) was synthesized by the reaction of Ti(SO4)2, H2C2O4(2H2O and N-(2-ammonioethyl)- piperazinium (AEPP) in aqueous solution. The single-crystal X-ray analysis has revealed that 1 crystallizes in the triclinic system, space group Pī with a = 9.1437(6), b = 11.4991(10), c = 11.6975(8)A, α = 96.2915(18), β = 107.998(3), γ = 104.276(4)°, V = 1110.35(14)A3, Z = 2, Dc = 1.807 g/cm3, F(000) = 618, μ = 0.815 mm-1, the final R = 0.0463 and wR = 0.1264 for 3718 observed reflections with I > 2σ(I). X-ray crystal-structure analysis suggests that compound 1 consists of [Ti4O4(C2O4)7]6- anion and two protonated N-(2-ammonioethyl)piperazinium cations. The anions are linked into an infinite chain through Ti4O4(C2O4)8 by sharing the oxalates as bridging ligands.  相似文献   
55.
1 INTRODUCTION Halometallates are the particularly suitable systems for designing the construction of unusual low-dimensional structural archetypes, from which peculiar electronic, thermal, catalytic and magnetic properties can arise. The syntheses of th…  相似文献   
56.
The title compound has been synthesized by the reaction of HgI2 and [(CH3)3- NCH2CH2N(CH3)3]I2 with pH = 7.5 at room temperature, and its crystal structure was determined by single-crystal X-ray diffraction analysis. The title compound crystallizes in monoclinic system, space group P21/c with a = 8.3075(8), b =15.8084(19), c =15.390(2)(°A), β = 95.192(4)o, V = 2012.9(4)(°A)3, Z = 2, Dc = 2.824 g/cm3, F(000) = 1502, C14H39N4O2Hg2I8, Mr = 1711.87, μ(MoKα) = 13.768 mm-1, the final R = 0.0465 and wR = 0.1293 for 3046 observed reflections with I > 2(I). The title compound consists of cations ([C8H22N2]2+) and anion (HgI42-), which are combined by static attracting forces to form the so-called organic-inorganic hybrid material.  相似文献   
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