Crystal Structure of Lithium Iodate

Abstract

The structure of lithium iodate was determined by using the oscillation and powder methods. Lithium iodate is hexagonal with 2 molecules per unit cell of $a=5.469\mathrm{}\pm 0.003\mathrm{A}$, $c=5.155\mathrm{}\mathrm{A}\pm 0.005\mathrm{A}$. The space group assigned is ${D_6}^6$ and the atom positions are: 2Li in (001/4) (003/4), 2I in (1/3 2/3 1/4) (2/3 1/3 3/4) and 6 O in $\mathrm{}\left(\mathrm{uu}0\mathrm{}\right)\mathrm{} \left(0\mathrm{}\overline{u}0\right) \left(\overline{u}00\right) \left(\overline{u}\overline{u}\frac{1}{2}\right) \left(0u\frac{1}{2}\right) \left(u0\mathrm{}\frac{1}{2}\right)$ with $u=\frac{1}{3}$. The structure is based on hexagonal closest packing, with the lithium and iodine atoms both lying within oxygen octahedra. The atomic distances are Li—O and I—O = 2.23A with lithium octahedra sharing faces with each other, one lithium and one iodine octahedra sharing only edges and two iodine octahedra only corners.