Alkylzinc compounds. Part I. Crystal structure of ethylzinc iodide

Abstract

The title compound crystallises in an orthorhombic cell with a= 21·17, b= 4·33, c= 5·38 Å, Z= 4, space group Pnma. The structure was solved from photographic data by the heavy-atom method and refined by the method of least-squares to R 0·11 for the 335 observed reflections. The four units of EtZnl in the unit cell lie on the mirror planes at y= 0·25 and 0·75. In the co-ordination polymer, each zinc atom is 2·64 Å from an iodine on the same mirror plane and 2·91 Å from iodines on mirror planes half-a-cell translation above and below. Zn–C is 1·95 Å and l–Zn–C, the angle formed by atoms on the same mirror plane, is 144·4°.

Molecular-weight measurements have indicated that monomeric ethylzinc iodide species are present in solution in ethyl iodide.