Effective distribution coefficients of a binary ideal solid solution controlled by kink kinetics

Effective distribution coefficients of a binary ideal solid solution growin g from dilute surroundings are derived for the steady state using a model i n which atoms attach and detach only at kink sites on a (0 0 1) surface of a simple cubic crystal. A system of equations is presented to give the step -edge, terrace, and bulk compositions in terms of attachment and detachment frequencies. The total net flux of atoms from the mother phase to kink sit es is also formulated as a function of these compositions and the frequenci es. Numerical solutions to the system of equations show that the step-edge, terrace, and bulk compositions are different from one another and that the step-edge, terrace, and bulk distribution coefficients will all approach u nity from their respective equilibrium values as the total net flux increas es. (C) 2001 Elsevier Science B.V. All rights reserved.