Fig. 4: Highly anharmonic optical mode at 11 meV.
From: Dimer rattling mode induced low thermal conductivity in an excellent acoustic conductor
a The experimental PDOS, vertically shifted for clarity. b. Calculated total and partial PDOS. c. Phonon dispersion of G = (022) Brillouin zone along [H,0,0] at 100 K. d–f Temperature dependence of phonon spectra for constant-Q scans of G = (022) Brillouin zone along [H,0,0] with q = 0, 0.2, 0.3 at 100, 300 and 450 K, respectively. The green dash lines highlight the energy shift of the peaks at heating.
