Dynamic heterogeneity in an orientational glass.

Area of Science:

• Condensed Matter Physics
• Materials Science
• Chemical Physics

Background:

• The CBr_nCl_4-n compound family aids in understanding microscopic mechanisms of glassy behavior.
• Certain members exhibit ordered phases with minimal disorder, suggesting potential for universal glass anomalies.

Purpose of the Study:

• To investigate the molecular dynamics of CBrCl3 using extensive simulations.
• To elucidate the microscopic mechanisms contributing to glassy behavior and relaxation times.

Main Methods:

• Extensive molecular dynamics simulations were performed on CBrCl3.
• Rotational autocorrelation functions were calculated to determine correlation times.
• Mean waiting and persistence times were computed from trajectory data.

Main Results:

• CBrCl3 molecules exhibit discrete cage-orientational jump motions, analogous to supercooled liquids.
• Simulation-derived correlation times align well with experimental dielectric results.
• Two distinct molecular groups within the monoclinic lattice display longer characteristic relaxation times.

Conclusions:

• The study elucidates microscopic mechanisms responsible for alpha- and beta-relaxation times in CBrCl3.
• The findings contribute to the understanding of molecular dynamics in glassy systems.
• The observed jump motions offer insights into universal features of glass anomalies.