Structural and electronic properties of liquid boron from a molecular-dynamics simulation

An ab initio molecular-dynamics simulation of liquid boron is presented. At the density 2 g cm-3 and the temperature T 2600 K, icosahedra are destroyed although atoms still form an open packing with sixfold coordination. Moreover, we found that most three-center covalent bonds, which make the -rhombohedral phase semiconducting, are destroyed. Furthermore, the estimated conductivity shows that boron undergoes a semiconductor-to-metal transition on melting, in agreement with the scarce experimental information.