Interfacial fluctuation effects at 3D wedge-wetting

We review recent advances concerning the nature of fluctuation effects occu rring at continuous filling transitions pertinent to fluid adsorption in we dge geometries. Unlike continuous (critical) wetting transitions for planar interfaces which are an extremely rare experimental phenomena, continuous filling transitions should be easily observable in the laboratory since the y can occur even if the underlying wetting transition is first-order. We ar gue that interfacial fluctuation effects at filling transitions are extreme ly strong and lead to a remarkable universal divergence of the interfacial roughness xi perpendicular to similar to (T-F - T) (-1/4) on approaching th e transition temperature TF, valid for all types of intermolecular forces. The results of renormalisation group and transfer matrix calculations of a novel interfacial model yielding a complete classification of the critical exponents for all dimensions and ranges of forces are given. (C) 2001 Elsev ier Science B.V. All rights reserved.