Abstract
The thermal expansion of single-crystalline is studied using high-resolution capacitance dilatometry. In addition to the orientational-ordering transition at 261 K, we observe a transition at ≊90 K due to the freezing in of orientational disorder, which has the character of a glass transition. The relaxation near is studied by varying the heating (cooling) rate over more than two decades. It is found to obey an Arrhenius behavior with =288±5 meV within a simple glass-transition model.
- Received 27 August 1992
DOI:https://doi.org/10.1103/PhysRevLett.69.3774
©1992 American Physical Society