SELF-DIFFUSION IN SINGLE-FILE PORES OF FINITE-LENGTH

Molecular dynamics simulation results are reported for single-file sel f-diffusion in pores of infinite and finite length. The model system i nvolves moderately dense, nonovertaking, hard-sphere fluids in cylindr ical pores, and the particle mobility is investigated as a function of time and pore length. It is shown that, while stationary Fickian diff usion in infinitely long pores with diffusely reflecting pore walls is nonexistent, a diffusivity may be defined for single-file pores of fi nite length. For pores of moderate length, it is also demonstrated tha t the self-diffusion coefficient scales as 1/root L where L is the por e length. (C) 1997 American Institute of Physics.