Crystal Structure of Ethylenebidiguanide Silver (III) Nitrate

Abstract

WHILE trying to prepare co-ordination compounds of ethylenebidiguanine with bivalent silver analogous to Cu(II) and Ni(II) by oxidation of a silver salt by sodium persulphate, Ray and Ghosh1 found that a complex compound was formed in which silver exhibited an oxidation state of three instead of the expected two. Tervalent silver is isoelectronic with Pd(II). Ray and Ghosh proved the trivalency of silver by showing experimentally the diamagnetic character of silver (III) ethylenebidiguanide complex salts, and on the basis of this evidence they proposed a square–planer configuration (dsp2 hybridization) for silver in these compounds, with the silver coordinated to four nitrogen atoms of the ligand. I have analysed the crystal structure of silver ethylenebidiguanide nitrate to confirm this proposal, and also because complete crystallographic work on a trivalent silver compound has not yet been reported.