Anomalously high-density glass of ethylbenzene prepared by vapor deposition at temperatures close to the glass-transition temperature

摘要

Molar volume V-m of ethylbenzene glass vapor-deposited on a metal substrate was studied as a function of deposition temperature T-d. Initial V-m of deposited sample showed a minimum at T-d around 0.86-0.91 times the glass-transition temperature T-g. Glass deposited at these or higher T-d close to T-g had V-m smaller than that estimated for supercooled liquid at the same temperature. Such dense glass showed relaxation accompanied with volume expansion at temperatures slightly higher than T-g. These observations are in harmony with those by Ediger and coworkers [S. F. Swallen et al., Science 315 (2007) 353] for vapordeposited glass made of much larger molecules.