Crystal structure, electronic structure and physical properties of cationic clathrate Se8P16Si30
作者单位：Key Laboratory of Transparent Opto-Functional Inorganic Materials Chinese Academy of Sciences (Shanghai Institute of Ceramics) Max Planck Institute for Chemical Physics of Solid State
会议名称：《中国晶体学会第五届全国会员代表大会暨学术大会（晶体生长分会场）》
会议日期：2014年
学科分类：081704[工学-应用化学] 07[理学] 070205[理学-凝聚态物理] 08[工学] 0817[工学-化学工程与技术] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 070301[理学-无机化学] 0702[理学-物理学]
摘 要：A new selenium cationic clathrate Ⅰ Si46-xPxSey(x ≤ 2y, 6x≤8) was synthesized from the elements and characterized by X-ray powder and single crystal diffraction, scanning electron microscopy, energy and wavelength dispersive X-ray spectroscopy(EDXS and WDXS). The magnetic susceptibility and heat capacity were investigated as well. Si46-xPxSey reveals a wide homogeneity range due to the presence of vacancies in the Se guest positions inside the smaller cage of the clathrate Ⅰ structure. The vacancy ordering in the structure of Si46-xPxSey causes the change of space group from Pm3n(ideal clathrate Ⅰ) to Pm3 accompanied by the redistribution of P and Si atoms over different framework atoms. Precise determination of the composition of Si46-xPxSey by WDXS showed slight but noticeable deviation(x ≤ 2y) of phosphorus content from the Zintl counting scheme(x = 2y). The compound is diamagnetic. Band structure and DOS calculations show semiconductors. The thermal and electrical transport properties will be investigated to confirm that.