Mean-square displacement from Mössbauer and x-ray data for solid krypton: A comparison of theory and experiment

The Mössbauer recoilless fraction is calculated from the lowest-order anharmonic-perturbation theory, the Green’s-function method, which sums the lowest-order anharmonic contributions to all orders, and the Monte Carlo method. In all cases we have employed a nearest-neighbor-interaction Lennard-Jones and Morse potential. Excellent agreement is shown to exist between the theory and the Mössbauer and x-ray experimental results.