CROSSOVER-BEHAVIOR OF ADSORPTION, SURFACE-TENSION, AND ORDER-PARAMETER PROFILE IN THE CRITICAL REGION

The renormalization-group method and epsilon-expansion are used to inv estigate the behavior of adsorption and order-parameter profile in the vicinity of the wall in a wide neighborhood of the point of second-or der transition. Crossover expressions for the adsorption and order-par ameter profile are derived in a first epsilon-approximation. At tau mu ch greater than Gi, the derived expressions transform to the appropria te formulas of the central-field theory, while at tau much less than G i they agree with the results derived within the scaling theory for a semi-infinite system. A phenomenological generalization of the derived expressions is constructed. A comparison is made between the results of this study and the known phenomenological expressions for the order -parameter profile and absorption in the critical region. The treatmen t of the experimental data for the Su,aden parameter reveals good agre ement between the derived expressions and experimental results.