Dielectric beta relaxations in the glassy state of salol?

The recently observed possibility to suppress the beta-relaxation intensity of omicron-terphenyl by annealing at temperatures below the glass transition guided us to ask, whether the absence of a dielectric beta process in many glass-forming materials, e.g., salol (phenyl salicylate), is a matter of the slow cooling rates usually employed to enter the glassy state. In order to assess this issue, we have quenched liquid salol to well below T-g at a rate of dT/dt = -490 K/min. Opposed to the case of cooling rates around -5 K/min or slower, this highly quenched sample displays a symmetric dielectric relaxation peak near f = 10(3) Hz with an appreciable relaxation strength, Delta epsilon = 6 X 10(-3). This novel feature of salol disappears irreversibly after a temperature excursion towards the glass transition at T-g = 220 K. (C) 1999 American Institute of Physics. [S0021-9606(99)50823-4].