A simple qualitative theory of the instability and reconstruction of surfaces of solids exhibiting a certain covalent component of bonding was considered. This theory was applied to the (2 x 1) Si(001) and (111) surfaces, with a possible extension to analogous surfaces of germanium and GaAs(001). It was proposed that Shockley surface states from the vicinity of the Fermi energy play a key role in the electron-phonon coupling.

Instability and (2 x 1) Reconstruction of Si(001) and (111) Surfaces - a Simple Approach. M.Tomášek: Theoretical Chemistry Accounts, 1988, 74[4], 331-7