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The thermal conductivity Κ(T) of glassy and supercooled liquid methanol, ethanol and of 1-propanol has been measured under equilibrium vapor pressure in temperature interval from 2 K to 160 K by the steady-state method. The metastable orientationally disordered crystal of ethyl alcohol is found to exhibit a temperature dependence of Κ(T) that is remarkably close to that of the fully amorphous solid, especially at low temperatures. In the case of propyl alcohol, our results emphasize the role played by internal molecular degrees of freedom as sources of strong resonant phonon scattering. For all samples here explored, the glass-like behavior of Κ(T) is described at the phenomenological level using the model of soft potentials. The thermal transport is then understood in terms of a competition between phonon-assisted and diffusive transport effects. The thermal conductivity Κ is thus a sum of two contributions: Κ = ΚI + ΚII, where ΚI is the acoustic phonon component dependent on the translational and orientational ordering of molecules, ΚII – is the phonon diffusion component corresponding to a non – acoustic phonon heat transfer in accordance with the Cahill – Pohl model. [ABSTRACT FROM AUTHOR]

Bulk phonon limited mobility in silicon based MOSFETs, have long been observed to demonstrate a -1/3rd dependence on the effective transverse field at room and higher temperatures. However, despite significant effort, existing phonon scattering models fail to reproduce this dependence. This paper reports on the impact of approximations used in the calculation of the intra-valley scattering rate in existing models which causes a much reduced dependence of phonon limited mobility on the effective field. An expression for scattering rate in the absence of such approximations is derived. The improvement of the new complex model is however, insufficient to match experiment. To improve the situation an empirical model is proposed with deformation potentials dependent on the inversion sheet concentration. [ABSTRACT FROM AUTHOR]