Thermoelastic Behavior of Orientationally Disordered Ammonium Iodide

Abstract

We have investigated the second order elastic constants of orientationally disordered NH₄I using an Extended Three Body Force Shell Model (ETSM) in the temperature range 250K≤T≤350K.The second order elastic constants (C₁₁, C₁₂ and C₄₄) obtained by us show an anomalous behaviour with the variation of temperature. The variation of the second order elastic constants with temperature is in good agreement with the measured data.