Elastic properties of a paramagnet: Application to NdVO4

Equations are developed which govern the behavior of all the pure transverse or longitudinal elastic modes in a paramagnet in the presence of an arbitrarily oriented applied magnetic field. Care is taken to include all finite strain and rotational effects. Explicit application to a Kramer's doublet at a site of $D_{2d}$ symmetry (e.g., NdV${\mathrm{O}}_4$) is made.