论文部分内容阅读
在水热条件下, 以SeO2、V2O5、MoO3、K2CO3、en(乙二胺)作为起始原料, 得到了标题化合物(H2en)2[Se2Mo5O21]2H2O, 利用IR、UV、荧光光谱、单晶-X射线衍射等方法对其进行了表征。结构测定表明, 该化合物属于正交晶系, 空间群: P212121, 化学式: C4H24- Mo5N4O23Se2, 晶胞参数: a = 12.1386(7), b = 17.7118(8), c =11.7092(5) ? V = 2517.4(2) ?, Z = 4, Dc = 2.987 g/cm3, Mr = 1133.89, m = 5.419 mm-1, F(000) = 2144, 最终结构偏离因子R = 0.0285, wR = 0.0400, S = 0.904。该化合物由2个双质子化的en、2个H2O分子以及杂多阴离子[Se2Mo5O21]4-组成。其中,杂多阴离子由5个畸变的MoO6八面体以共边或共顶点形式连接构成一个平面骨架; 2个畸变的SeO3四面体和MoO6八面体以共顶点形式连接, 且位于平面的两侧;质子化的en位于4个[Se2Mo5O21]4-离子围成的四面体空位中, 与杂多阴离子和水分子通过氢键连接成无限三维结构。最后我们用B3LYP方法研究了阴离子簇的电子结构。
The title compound (H2en) 2 [Se2Mo5O21] 2H2O was obtained under hydrothermal conditions using SeO2, V2O5, MoO3, K2CO3 and en (ethylenediamine) as starting materials. X-ray diffraction and other methods to characterize it. The structure determination shows that the compound belongs to the orthorhombic system with the space group P212121 and the chemical formula C4H24-Mo5N4O23Se2. The unit cell parameters are a = 12.1386 (7), b = 17.7118 (8) and c = 11.7092 The final structure deviation factor R = 0.0285, wR = 0.0400, S = 0.904 (2), Z = 4, Dc = 2.987 g / cm3, Mr = 1133.89, m = 5.419 mm- . The compound consists of two di-protonated en, two H2O molecules and a heteropolyanion [Se2Mo5O21] 4-. Among them, the heteropolyanions are composed of five distorted MoO6 octahedra connected by a common edge or a common apex; the two distorted SeO3 tetrahedrons and the MoO6 octahedrons are connected in a common vertex and located on both sides of the plane; Protonated en located in 4 [Se2Mo5O21] 4 - ions enclosed tetrahedral vacancies, and heteropolyanions and water molecules connected by hydrogen bonds into an infinite three-dimensional structure. Finally, we used the B3LYP method to study the electronic structure of anionic clusters.