A theoretical investigation of ideal III-V (211) surfaces

Ab-initio methods are used for the first time to investigate the geometrica l and electronic structure of ideal III-V (211) semiconductor surfaces. Ver y large relaxations are found, and the (211)A and (211)B type surfaces show extensive differences in the atomic positions of the topmost atomic layers . Smaller bur distinct differences in atomic relaxations between GaAs and o ther III-V systems are also found and properly explained. All surfaces beco me metallic due to the dangling bonds, and a variety of surface states and resonances are investigated. (C) 2000 Elsevier Science B.V. All rights rese rved.