MULTI-INTERACTION MEAN-FIELD RENORMALIZATION-GROUP

We present an extension of the previously proposed mean-field renormal ization method to model Hamiltonians that are characterized by more th an just one type of interaction. The method rests on scaling assumptio ns about the magnetization of different sublattices of the given latti ce and it generates as many flow equations as coupling constants witho ut arbitrary truncations on the renormalized Hamiltonian. We obtain go od results for the test case of Ising systems with an additional secon d-neighbor coupling in two and three dimensions. An application of the method is also done to a morphological model of interacting surfaces introduced recently by Likes, Mecke, and Wagner [J. Chem. Phys. 102, 9 350 (1995)].