Ca_2B_2O_5的电子结构和能带结构

The Electronic Energy Band Structures of Pyroborate Calcium

合成了标题化合物,在已测晶体结构的基础上,利用合组态作用的INDO/S方法计算了其电子能带结构;利用态求和方法计算了微结构分子的线性极化率及其晶体的平均折射率.分析结果表明,价带主要由B^(3+)和O^(2-)离子的价轨道的贡献,导带底部主要由Ca^(2+)离子轨道的贡献,从O^(2-)离子到Ca^(2+)离子的电荷转移对线性极化率起主要贡献.

The title compound has been synthesized. On the basis of the determined single - crystal structure data of this compound, the electronic structures are calculated using the INDO/S method with configuration interactions, following combination with the sum - over - state method. The linear polarizability of micro - species Ca2B2O5 is obtained, and the average refractive index is estimated for bulk Ca2B2O5. It is shown that the valence band has the contributions from the 2p orbitals of B and O atoms, while the low edge of conduction band has the main contributions from the Ca atoms, and the charge transfers from the oxygen atomic orbital to calcium atomic orbital make the significant contributions to the polarizability.