Structure and growth of stearate monolayers on calcite: First results of an in situ X-ray reflectivity study

The adsorption of organic molecules at mineral-fluid interfaces has a profo und influence upon geochemical reaction and transport processes, yet little is known about the in situ structures or properties of organic layers at m ineral-fluid interfaces. We describe an X-ray reflectivity study of stearat e monolayers adsorbed at the calcite surface from methanolic solutions. Usi ng these measurements we are able to determine important aspects of the in situ structure, bonding, adsorption, and growth mechanisms of stearate mono layers. The experimental approach demonstrated here can be applied widely i n studying the interaction of organic molecules with mineral surfaces in aq ueous systems. Copyright (C) 1999 Elsevier Science Ltd.