The diffusion properties and microscopic diffusion mechanisms in liquid B2O3 under pressure were studied by ab initio molecular dynamics simulations. It was found that diffusivities of liquid B2O3 exhibited an anomalous pressure dependence. The diffusion coefficients of liquid materials usually decreased with pressure. However, that of liquid B2O3 increased with increasing pressure up to about 10GPa. Additionally, the diffusivity of boron became about twice as large as that of oxygen under pressures above 20GPa. These anomalous pressure dependences were strongly related to the microscopic atomic diffusion in liquid B2O3.

Ab initio Molecular Dynamics Study of Diffusion Mechanism in Liquid B2O3 Under Pressure. Ohmura, S., Shimojo, F.: Journal of Physics - Conference Series, 2012, 402[1], 012012