ATOMIC AND ELECTRONIC-STRUCTURES OF NEUTRAL AND CHARGED BORON AND BORON-RICH CLUSTERS

Ab initio molecular orbital theory based on both density functional fo rmalism and quantum chemical methods has been used to calculate the eq uilibrium geometries, binding energies, ionization potentials, fragmen tation patterns, and electronic structures of neutral and charged boro n clusters containing up to six atoms. Calculations have also been per formed on restricted geometries for BnX (n = 1,5,12; X=Be, B, C) and B -20 clusters to see if clusters can be designed so as to increase thei r stability. Energetics of doubly charged B-n(++) clusters have also b een studied to find the critical size for Coulomb explosion. The resul ts are compared with existing experimental and theoretical data. (C) 1 997 American Institute of Physics.