Amorphization of crystalline B2O3 by molecular dynamics simulations

Abstract

Molecular dynamics (MD) simulations have been used to produce crystalline B2O3 with some defects. The sudden drop in the enthalpy is considered a clue for the formation of crystalline structure. The appearance of crystalline peaks in the radial distribution function that are consistant with that obtained from x-ray diffraction is also another method to prove the existence of crystalline structure. The amorphization of crystalline B2O3 is carried out by a successive insertion of sodium-oxygen-sodium ions into the MD cell with different velocities. It is found that the number of created defects in the structure depends on the number and the velocity of the inserted ions. Moreover, the relaxation time has a major effect on the created defects.The irreversible transition from the amorphous to crystalline state is also investigated. The extraction of Na-O-Na ions from the MD cell under the same condition of insertion failed to achieve this type of transition.