Factors contributing to the glass-forming ability of a simulated molecular liquid

The time scales of crystallization of two model liquids, an atomic liquid and a molecular liquid of bent trimers originally introduced as a model of the glass the former o-terphenyl, are determined using molecular dynamics simulations. The molecular liquid is found to have a minimum crystallization time, on supercooling, that is 10(4) times larger than that of the atomic liquid. We present evidence that this enhanced glass-forming ability is due, in equal parts, to the slower dynamics and the larger crystal-liquid interfacial free energy in the molecular liquid.