Temperature Dependence of The Raman Frequency Shifts Related to The Specific Heat and Thermal Expansion Close To I-II Phase Transition in S-Triazine.

摘要

A linear variation of the specific heat Cp with the frequency shifts 1(32) is established for the @ OT }, Raman modes I-V at various temperatures (P=0) close: to I-II phase transition in s-triazine (7,=198 K). As an extension of this work, the temperature dependence of the thermal expansion a, is predicted from the frequency shifts and by the y, values deduced for the Raman modes studied close to the I-II phase transition in s-triazine. Our predicted a, can be examined by the thermodynamics measurements of the thermal expansion at various temperatures at zero pressure in both phases I and II of s-triazine.