Accelerated Aging in Ultrathin Films of a Molecular Glass Former

作者:Sepulveda A; Leon Gutierrez E; Gonzalez Silveira M; Rodriguez Tinoco C; Clavaguera Mora M T; Rodriguez Viejo J*
来源:Physical Review Letters, 2011, 107(2): 025901.
DOI:10.1103/PhysRevLett.107.025901

摘要

We report the thermodynamic measurement of the enthalpy released during the aging of supported films of a molecular glass former, toluene, at temperatures well below the glass transition temperature. By using microfabricated devices with very short equilibration times (below 1 s), we evidence a remarkable variation of the relaxation rate on decreasing film thickness from 100 nm down to a 7 nm thick film. Our results demonstrate that surface atoms are more efficient than bulk atoms in attaining low energy configurations within the potential energy landscape.

  • 出版日期2011-7-7