Calculation of the chemical potential of chain molecules using the staged particle deletion scheme

A formulation is presented for the calculation of the chemical potential of chain molecules from molecular simulation based on the staged deletion of a test molecule. This formulation is an extension of a formulation presente d recently [Boulougouris , Mol. Phys. 96, 905 (1999)] for the case of spher ical molecules. An analytical method for the calculation of the volume acce ssible to a hard-sphere chain molecule is used together with the excluded v olume map sampling technique. The new method is applied to a fluid of tange nt sphere dimers and to ethane under various conditions. NPT, NVT, and Gibb s ensemble Monte Carlo simulation results are presented. Extensive comparis on is made against calculations with the Widom test particle insertion meth od. In all cases, the new method results in considerable savings in CPU tim e. (C) 2001 American Institute of Physics.