The non-Debye excess heat capacities of binary lithium borate glasses with different Li2O compositions of x = 8, 14 and 22 (mol%) are investigated to understand origin of the boson peak. The low-temperature heat capacities are measured between 2 and 50 K by a relaxation calorimeter. The experimental non-Debye heat capacities with x = 14 is successfully reproduced using the excess vibrational density of states measured
by inelastic neutron scattering. This finding indicates that the non-Debye heat capacities of lithium borate glasses originate from the excess vibrational density of states measureable by inelastic neutron scattering. Moreover, it is demonstrated that all of the excess heat capacity spectra lie on a single master curve by the scaling using boson peak temperature and intensity.
(J. Non-Cryst. Solids, 357, 534-537 (2011))
Heat capacities of the ordered and disordered crystalline p-chloronitrobenzene, the latter of which is
in glassy state below 245 K, were measured down to 0.3 K.
The heat capacity of the disordered state exceeds
5 times of that of the ordered phase at 1 K.
Temperature dependence of the heat capacity
of the disordered state is weaker than that expected
by the Debye model.
No hump in Cp/T3 was observed for the
The behavior is discussed in relation to
low-energy excitation in amorphous materials.
(Solid State Commun., 118, 611-614 (2001))
Return to Rigid Disorder in Simple Molecular Solids
Return to Kazuya's Home Page