Wetting on non-planar and heterogeneous substrates

We report results of wetting on non-planar and heterogeneous surfaces calcu lated from an effective interfacial Hamiltonian model. The lack of translat ional invariance along the substrate induces a series of structural changes of the interface such as unbending and a number of nonthermodynamic singul arities and can modify the location of the wetting transition. We show that the order of the wetting transition in the planar homogeneous system stron gly affects the behaviour of the non-planar and heterogeneous surfaces.