Matrix reactions of Na, K, Rb, and Cs atoms with N2O: Infrared spectra and geometries of K2O, Rb2O, and Cs2O

Abstract

Reactions of the heavy alkali metal atoms with N₂O have been studied using the matrix reaction technique. No sodium oxides were produced; however, the metals K, Rb, and Cs yielded products with infrared absorptions appropriate for assignment to ν₃ of the M–O–M high‐temperature molecules. The identification of these molecules is based on oxygen isotopic shifts and on experiments codepositing two different alkali metals. Apex angle calculations indicate that K₂O and Rb₂O have valence angles in the 160°–180° range and that the Cs₂O angle is approximately 130°–140°. This trend is rationalized on the basis of increasing metal‐metal bonding with the more polarizable alkali cation. The KO and CsO fundamentals were observed at 384 and 314 cm⁻¹ in solid nitrogen.