Role of lone-pair electrons in producing minimum thermal conductivity in nitrogen-group chalcogenide compounds.
Role of lone-pair electrons in producing minimum thermal conductivity in nitrogen-group chalcogenide compounds.
复制标题
DOI：
10.1103/physrevlett.107.235901
复制
发表时间：
2011-11
影响因子：
8.6
通讯作者：
E. J. Skoug;D. Morelli
中科院分区：
文献类型：
--
作者：
E. J. Skoug;D. Morelli
具有极低晶格导热率 (κ(L)) 的完全致密结晶固体对于热电能量转换和热障涂层等应用具有实际重要性。在这里，我们表明，在含有名义上三价 VA 族元素的硫族化物化合物中，孤对电子可以产生最小 κ(L)。孤对电子和相邻硫族离子之间的静电排斥在晶格中产生非谐性，其强度由孤对电子轨道的形态和VA族原子的配位数决定。
Fully dense crystalline solids with extremely low lattice thermal conductivity (κ(L)) are of practical importance for applications including thermoelectric energy conversion and thermal barrier coatings. Here we show that lone-pair electrons can give rise to minimum κ(L) in chalcogenide compounds that contain a nominally trivalent group VA element. Electrostatic repulsion between the lone-pair electrons and neighboring chalcogen ions creates anharmonicity in the lattice, the strength of which is determined by the morphology of the lone-pair orbital and the coordination number of the group VA atom.