Ab initio Monte Carlo:: application to Li8

An ab initio-based Monte Carlo scheme is developed and implemented to investigate structural and thermal properties of lithium clusters. The scheme combines a hybrid Hartree-Fock/density functional electronic structure treatment with a Monte Carlo sampling of the nuclear configuration space. Structural forms (isomers) of the Li(8 )cluster are obtained and its thermal properties are analyzed. The analysis is carried out in terms of probability distributions of the cluster potential (configurational) energy, average potential energy and configurational heat capacity, all considered as a function of the cluster temperature. An estimate of the temperature characterizing the onset of isomer 'coexistence' in L(8) is given. (C) 1998 Published by Elsevier Science B.V. All rights reserved.