SEMINAR
The State Key Lab of
High Performance Ceramics and Superfine Microstructure

　　Shanghai Institute of Ceramics, Chinese Academy of Sciences

　　中 国 科 学 院 上 海 硅 酸 盐 研 究 所 高 性 能 陶 瓷 和 超 微 结 构 国 家 重 点 实 验 室 

　　Topological features of chemical bonding and thermoelectric ability of materials

　　Prof. Yuri Grin

　　Max-Planck-Institut für Chemische Physik fester Stoffe, Dresden, Germany　　

　　时间：2015年4月21日（星期二）上午10:00

　　地点：2号楼607会议室

　　联系人：陈立东 4804

　　报告摘要：

　　The electron-engineering approach in the development of new thermoelectric materials is well established strategy. In contrary, the phonon-engineering part offers still a play yard for new chemical ides [1]. Crystallographic features which reflect structural complexity are considered as one of the factors effecting thermoelectric ability of substances. Structural complexity of thermoelectric materials may be described taking into account either their basic crystallographic characteristics as point symmetry, number of atoms per unit cell, or considering chemical and positional order/disorder [2,3], or even including into considerations thermodynamic phase diagrams and formation conditions of the compounds [4]. Large number of atoms in the unit cell was one of the first of such descriptors, which was introduced to the consideration of the thermal conductivity of thermoelectric materials [5]. The quantum chemical bonding descriptors were found to be suitable analytical tools to get more insight into the thermoelectric behavior. Spatial separation of the regions with different kind of atomic interactions in a crystal structure is a fingerprint for enhanced thermoelectric ability. For the compounds with the characteristic structural and bonding features, e.g. clathrates with their cage structures, oxides with crystallographic share planes or halcogenides or pnictides with the (pseudo) lone-pair interactions [6], structural and bonding complexity opens an opportunity to influence more directly the thermal conductivity separating - at least partially – its lattice and electronic parts.

　　[1] S. Bühler-Paschen, C. Godart, Yu. Grin. In: Complex Metallic Alloys: Fundamentals and Applications, WILEY-VCH, 2011, 365ff.

　　[2] K.Urban,M. Feuerbacher. J. Non-Cryst. Solids 334&335(2004) 143.

　　[3] J. Dshemuchadse, W. Steurer. Acta Crystallogr A69 (2013) 628.

　　[4] G. Kreiner, Yu. Grin. Chemie&More (2011) 1.

　　[5] G. A. Slack. In: Thermoelectric Handbook, CRC, Boca Raton, FL, 1995, 407ff.

　　[6] S. Wang, J. Yang, L. Wu, P. Wei, J. Yang, W. Zhang, Yu. Grin. Chem. Mat. 27 (2015) 1071.