First-principles total-energy calculations were used to investigate the (2 x 1), (1 x 2), (2 x 2), (4 x 2) and (2 x 4) reconstructions of Cd- and Se-terminated CdSe(001) and (111) surfaces as a function of the surface stoichiometry and the Cd chemical potential. It was found that Cd dimers existed on the (001) surface, and Se tetramers on the (111) surface. Upon comparing the surface formation energies as a function of the Cd chemical potential, μCd, it was found that the Cd-vacancy and Se-vacancy (2 x 2) structures were energetically favourable for the Cd-terminated (001) surface at high μCd and the Se-terminated (001) surface at low μCd, respectively. However, a Se-tetramer (2 x 4) structure was more favourable than the vacancy structure for the Se-terminated CdSe(111) surface over almost the whole range of allowed μCd.

First-Principles Studies of the Atomic Reconstructions of CdSe (001) and (111) Surfaces. L.Zhu, K.L.Yao, Z.L.Liu, Y.B.Li: Journal of Physics - Condensed Matter, 2009, 21[9], 095001