Raman linewidths calculated as a function of temperature in NaNO(2)


KARACALİ H., YURTSEVEN H. H. , Kiraci A.

PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS, vol.246, no.5, pp.1124-1131, 2009 (SCI-Expanded) identifier identifier

Abstract

The temperature dependence of the damping constant is calculated for some Raman modes in NaNO(2) using the soft mode-hard mode coupling model and the energy fluctuation model. The damping constant is fitted to the measured Raman bandwidths of those modes, which is well described by the soft mode-hard mode coupling model. The values of the activation energy are extracted from the damping constant for the Raman modes, which are much greater than k(B)T(C) = 0.04 eV for NaNO(2) close to the transition temperature (T(C) = 436 K). This is an indication that NaNO(2) undergoes an order-disorder phase transition. (C) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim