标题：First-principles study of bulk and (001) surface of TiC
作者：Fang Li-hong; Wang Li; Gong Jian-hong; Dai Hong-shang; Miao De-zhuang
作者机构：[Fang Li-hong; Dai Hong-shang; Miao De-zhuang] Shandong Univ, Minist Educ, Key Lab Liquid Struct & Hered Mat, Jinan 250061, Peoples R China.; [Wang 更多
通讯作者地址：[Wang, L]Shandong Univ, Minist Educ, Key Lab Liquid Struct & Hered Mat, Jinan 250061, Peoples R China.
来源：TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
关键词：first-principles; TiC; charge transfer; structural relaxation
摘要：The structural and electronic properties of bulk and (001) plane of TiC were investigated by the first-principles total-energy pseudopotential method based on density functional theory. The calculated bulk properties indicate that bonding nature in TiC is a combination of ionicity, covalency and metallicity, in which the Ti-C covalent bonding is the predominate one. The calculated results of structural relaxation and surface energy for TiC(001) slab indicate that slab with 7 layers shows bulk-like characteristic interiors, and the changes of slab occur on the outmost three layers, which shows that the relaxation only influences the top three layers. Meanwhile, the strong Ti-C covalent bonding can be found in the distribution of charge density on the (110) and (001) planes. Ti-C covalent bonding is enhanced by the charge depletion and accumulation in the vacuum and the interlayer region between top two atomic layers.