Determination of optical properties of hexagonal lithium iodate crystal by use of NQR and IR spectroscopy

The NQR Zeeman effect of ¹²⁷I (± $\text{1}\text{2}$ ←→ ± $\text{3}\text{2}$ transition) for the LiIO₃ crystal of hexagonal modification has been investigated, and the EFTG asymmetry parameter for nuclei of ¹²⁷I determined. Measurements of optical properties of the z-cut crystal in polarized light within the region of stretching vibrations and their overtones for IO^?₃ revealed that transmission (reflection) depends on the direction of the incident light wave electric vector. The results obtained indicate that crystals of LiIO₃ grown from aqueous solutions show anomalous biaxiality.