O.A. Korolyuk, A.I. Krivchikov, I.V. Sharapova, and O.O. Romantsova
B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine 47 Lenin Ave., Kharkov 61103, Ukraine
Received January 26, 2009
Thermal conductivity coefficient к(T) of two crystalline (orientationally-ordered and orientationally-disordered) phases of pure methanol (at temperatures from 2 K to Tm , Tm is the melting temperature), CH3OH + 6.6 % H2O glass from 2 K to Tg , Tg is the glass transition temperature and a supercooled liquid from Tg to 120 K has been measured under equilibrium vapor pressure. The dependence к(T) is described approximately as a sum of two contributions: кI(T) describing heat transport by acoustic phonons and
кII(T) —by localized high-frequency excitations. The temperature dependences of the thermal conductivity of primary monoatomic alcohols CH3OH, C2H5OH, and C3H7OH in the glass state have been compared. Different
mechanisms of phonon scattering in the crystalline phases and glass have been analyzed. The кII(T) has been calculated within the Cahill–Pohl model. There is an anomaly of the thermal conductivity of the glass state near Tg (a smeared minimum in the к(T) — curve).
PACS: 66.70.–f Nonelectronic thermal conduction and heat-pulse propagation in solids; thermal waves; PACS: 63.20.–e Phonons in crystal lattices; PACS: 63.50.–x Vibrational states in disordered systems.