|Title||Accelerated Aging in Ultrathin Films of a Molecular Glass Former|
|Publication Type||Journal Article|
|Year of Publication||2011|
|Authors||Sepúlveda, A, Leon-Gutierrez, E, Gonzalez-Silveira, M, Rodríguez-Tinoco, C, Clavaguera-Mora, MT, Rodríguez-Viejo, J|
|Journal||Physical Review Letters|
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.
|Short Title||Phys. Rev. Lett. 107, 025901 (2011)|