Refinement of β-LiIO 3 crystal structure by use of zeeman effect on the NQR line and ir-reflection spectra

Abstract

The NQR Zeeman effect of 127I quadrupole resonance (± 1 2 ↓ ± 3 2 transition) and the polarized IR spectra of a single crystal of β-LiIO 3 have been studied. The z-axes of the EFG orientation in the unit cell were determined; the EFG asymmetry parameter for the 127I nuclei was refined giving η = 0.027 ± 0.003 at 300 K for β-LiIO 3. The dichroic ratio in the (100) crystal plane over the I-O stretching vibration region has been measured from polarized spectra and calculated on the basis of an “oriented gas” model by the use of refined structural data. Comparison of some spectral, structural and quantum-chemical characteristics of both β- and α-modifications of LiIO 3 crystal has been made.