This work investigates the outcomes of three thermoelastic theories on the reflection/refraction of elastic waves due to incident, coupled longitudinal and coupled shear waves from a plane interface between two microstretch thermoelastic diffusion solid halfspaces. The propagation of seven basic waves consisting of five longitudinal and two shear waves has been explored using the boundary conditions. The amplitude and energy ratios of the reflected and refracted waves are obtained analytically and numerically for the incident coupled longitudinal and coupled shear waves. We have seen that the longitudinal wave corresponding to micropolar does not reflect and refract from the interface. The variations of these ratios with respect to the angle of incidence based on GL theory, LS theory and CT theory are depicted for a particular specimen. The amplitude and energy ratios of the reflected and refracted coupled longitudinal waves for the incident, coupled longitudinal waves decrease with the increase of the angle of incidence. Some special cases have been deduced from the present formulation