The reliability of a recently developed potential model is tested by e
xtending the study to various anharmonic properties, e.g., third and f
ourth-order elastic constants, Gruneisen parameters, and the pressure
derivatives of second-order elastic constants of hydrides and deuterid
es of lithium and sodium. A comparison of the calculated properties wi
th the limited experimental results and other theoretical estimates gi
ves an indication of the applicability of the derived potential in the
study of crystal anharmonicity. However, the need for further experim
ental data is stressed in order to judge clearly the reliability of th
e present calculations for all the compounds.