Soft X-ray emission spectroscopy study of electronic structure of sodium borosilicide Na8B74.5Si17.5.
Soft X-ray emission spectroscopy study of electronic structure of sodium borosilicide Na8B74.5Si17.5.
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软X射线发射光谱研究硼硅化钠Na8B74.5Si17.5的电子结构。
DOI：
10.1093/jmicro/dfx132
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发表时间：
2018
期刊：
影响因子：
1.8
通讯作者：
K. Kimoto
中科院分区：
文献类型：
--
作者：
M. Terauchi;H. Morito;H. Yamane;S. Koshiya;K. Kimoto
用软X射线发射光谱研究了硼硅化钠Na8B74.5Si17.5的化学键状态。该材料由B12团簇网络和特征硅链[-Si-（Si-Si）3-Si-]组成，它们之间以sp3键连接，键距和键角与立方Si晶体相近。该材料的B K发射光谱与α-r-B、B_4 C和β-r-B的B_（12）团簇材料相似，但强度分布较宽。较宽的强度分布可能是由于B12团簇中B-B键长的变化。实验上导出了[-Si-（Si-Si）3-Si-]硅链的态密度（DOS）。它具有与立方硅的L-发射谱相似的能量宽度和强度分布的峰肩结构。从实验光谱和相应的计算DOS的比较，Si链和B12团簇网络之间的共价键。用WIEN 2k程序计算了Na_8B_（74.5）Si_（17.5）的态密度，讨论了它们之间的关系。
Chemical bonding state of sodium borosilicide Na8B74.5Si17.5, which is a new member of B12-cluster materials, is investigated by soft X-ray emission spectroscopy. The material is composed of B12 cluster network and characteristic silicon chains of [-Si-(Si-Si)3-Si-] connected by sp3 bonding, in which bonding distances and bonding angles are close to those in cubic Si crystal. B K-emission spectrum of the material showed a similar but a broader intensity distribution with those of B12 cluster materials of α-r-B, B4C and β-r-B. The broader intensity distribution can be due to a variation of B-B bond length in B12 cluster. The density of states (DOS) of silicon chains of [-Si-(Si-Si)3-Si-] was experimentally derived. It shows a similar energy width, and peak or shoulder structures in intensity distribution with those of L-emission spectrum of cubic Si. From comparisons between experimental spectra and corresponding calculated DOS, covalent bonding between Si chain and B12 cluster network is suggested. Those are discussed by using a theoretically calculated density of state of Na8B74.5Si17.5 by using WIEN2k code.