Molecular dynamics simulations were carried out in order to investigate the structure and transport properties of boron oxide melt, as a function of pressure. The simulations revealed a rapid initial increase in the diffusion coefficients of boron and oxygen ions for 5 to 7GPa, followed by a slower increase from 7 to 14GPa. The increase in ion diffusivities was correlated with an increase in the proportion of BO4 to BO3 units. These results help to explain an increase in the growth rate of boron sub-oxide (B6O) crystals, observed from B2O3-B6O melts, in the 0 to 4GPa pressure range.

Molecular Dynamics Study of the Self-Diffusion of Ions in B2O3 Melt at High Pressure. Diefenbacher, J., McMillan, P.F.: Journal of Physical Chemistry A, 2001, 105[34], 7973-8