A Monte Carlo study of the phase transitions on Ge(001) was carried out using the Ising model with axial next nearest neighbours interaction. It was shown that the transition between high and low temperature phases occurred via an intermediate modulated phase for definite relations of the interaction parameters. The period of the modulated phase depends on the temperature. The low temperature phase was found to be a c(4 x 2) structure. A phase diagram was obtained.

Monte Carlo Study of Surface Reconstruction in Ge(001). V.E.Zubkus, P.J.Kundrotas, S.N.Molotkov, V.V.Tatarskij, E.E.Tornau: Surface Science, 1991, 243[1-3], 295-302