Reflection coefficient null of acoustic waves at a liquid–anisotropic‐solid interface

he reflection coefficient of acoustic waves incident on a liquid–solid interface from the liquid side is numerically calculated for a general anisotropic solid oriented in any arbitrary direction. The reflection coefficient depends, in general, on polar and azimuthal angles of incidence. Results are presented for various crystalline materials of different symmetry classes. A null in the reflection coefficient amplitude is detected at a particular incidence angle for every anisotropic material that supports pseudosurface waves. The null in the reflection corresponds to the excitation of the pseudosurface wave on the interface surface, and it has typically a very narrow angular aperture. The angular position of the null is very critical and highly dependent on the elastic parameters of the anisotropic solid.