Study of the stable structures of Ga4As4 cluster using FP-LMTO MD method

Full-potential linear-muffin-tin-orbital molecular-dynamics calculations ha ve been performed to investigate the structures and energies of a Ga4As4 cl uster. We obtained 28 stable structures for a Ga4As4 cluster, including all three structures considered by Al-Laham and Raghavachari [J. Chem. Phys. 9 8, 8770 (1993)], who used an ab initio molecular-orbital method. The sequen ce of stability of the three structures we obtained is the same as theirs. However, the ground state we obtained is an edge-capped pentagonal bipyrami d, the energy of which is much lower than that of the C-i symmetry structur e proposed by Al-Laham and Raghavachari.