Mössbauer Effect and the Dynamics of the Molecular Solid SnI4

The available Mössbauer data on ¹¹⁹Sn and ¹²⁹I in solid SnI₄ are analyzed in terms of a detailed molecular‐dynamical model to give characteristic Einstein temperatures for the intermolecular translational and rotational vibrations: ${\theta }_l\text{\hspace{0.17em}=\hspace{0.17em}44°K}$ and ${\theta }_{\mathrm{rot}}{\text{\hspace{0.17em}=\hspace{0.17em}66°K. θ}}_l$ is very close to the observed (ir) antitranslational vibrational frequency (48°K) of the eight molecules in the unit cell. The calculated specific heat, based on the present analysis, is consistent with the experimental results for $C_p$ .