STRUCTURAL AND ELECTRONIC-PROPERTIES OF THE MOS2(10(1)OVER-BAR0) EDGE-SURFACE

Ab-initio investigations of the structural and electronic properties o f the clean MoS2(010) edge-surface are presented. It is shown that the bulk-terminated surface remains stable in vacuum up to temperatures o f T similar to 700 K, with only modest relaxations of the surface atom s. In contrast to the semiconducting bulk, the (010) surface shows a f inite density of states at the Fermi level. On the unsaturated Mo-surf ace atoms, the most intense surface states are empty d(yz) and d(x2-y2 )-type states just above the Fermi level, demonstrating the acceptor p roperties of the surfaces. On the unsaturated S sites, (p(y)+/-p(z)) s tates at the Fermi level promote a tendency to S-S pairing. (C) 1998 E lsevier Science B.V. All rights reserved.