Electronic structure of the alpha and delta phases of Bi2O3: A combined ab initio and x-ray spectroscopy study
Electronic structure of the alpha and delta phases of Bi2O3: A combined ab initio and x-ray spectroscopy study
复制标题
DOI：
10.1103/physrevb.73.235104
复制
发表时间：
2006-06
影响因子：
3.7
通讯作者：
A. Walsh;G. Watson;D. Payne;R. G. Edgell;Jinghua Guo;P. Glans;T. Learmonth;Kevin E Smith
中科院分区：
文献类型：
--
作者：
A. Walsh;G. Watson;D. Payne;R. G. Edgell;Jinghua Guo;P. Glans;T. Learmonth;Kevin E Smith
α-Bi 2 O 3是Bi 2 O 3在室温下的化学稳定相。我们采用梯度修正密度泛函理论（DFT）、沿着的X射线光电子能谱和O-K壳层X射线吸收和发射光谱对它的电子结构进行了理论和实验研究。我们研究的性质，在α-Bi 2 O 3键合，特别是探索的性质的立体化学活性Bi电子孤对。发现Bi的6s态集中在价带的底部，但对Bi上的孤对电子有贡献的态来自价带的顶部。发现O 2 p和Bi 6s态之间的混合是在Bi上产生非对称密度的关键。孤对在快离子导体δ-Bi 2 O3中的作用也进行了研究，通过计算的电子结构与，和对齐的氧空位。对齐的空缺沿着的结果在最积极有利的配置的δ相，相反，以前的力场计算和静电参数，有利于对齐。
alpha-Bi2O3 is the thermodynamically stable phase of Bi2O3 at room temperature. We have performed a theoretical and experimental investigation of its electronic structure using a combination of gradient corrected density functional theory (DFT), along with x-ray photoemission and O-K shell x-ray absorption and emission spectroscopies. We examine the nature of bonding in alpha-Bi2O3 and in particular explore the nature of the stereochemically active Bi electron lone pair. The Bi 6s states are found to be concentrated at the bottom of the valence band but the states contributing to the lone pair on Bi are derived from the top of the valence band. Mixing between O 2p and Bi 6s states is found to be crucial in producing the asymmetric density on Bi. The role of the lone pair in the fast ion conductor delta-Bi2O3 is also investigated, through calculation of the electronic structure with , , and alignment of oxygen vacancies. Alignment of the vacancies along results in the most energetically favorable configuration of the delta phase, contrary to previous force field calculations and electrostatic arguments which favor the alignment.