Karaçalı, HüseyinYurtseven, Hasan Hamit2021-06-232021-06-2320060019-4522https://hdl.handle.net/20.500.12491/4319https://www.scopus.com/inward/record.uri?eid=2-s2.0-33845617172&partnerID=40&md5=7c9c854e3dd3c6dbadea9dba90a8aa04This study gives our relations between the specific heat C P and the Raman frequency shifts (1/v)(partial derivative v/partial derivative T)(p) for the lattice modes of v(5) (144 cm(-1)) and v(5) (174 cm(-1)), when the mode Gruneisen parameter gamma(p) depends on the temperature near. the lambda-transition in NH4Cl (T-lambda = 242.5 K, P = 0). From our linear relations between C-p and (1/v)(partial derivative v/partial derivative T)(p), we deduce the values of the slope (dP/dT)(lambda) for both lattice modes in this crystal. Our (dP/dT)(lambda) values remain almost the same as those which we calculate when gamma(p) is taken as a constant close to the lambda-transition in NH4Cl. Our calculated values for (dP/dT)(lambda) are reasonable in compared to the experimental values.eninfo:eu-repo/semantics/closedAccessMode Gruneisen ParameterAmmonium ChlorideLambda-Transition PointPartial DerivativeCrystalParameter GammaArticle8311109711022-s2.0-33845617172Q4WOS:000243095200006Q4