Matrix isolation study of the interaction of excited neon atoms with O3: Infrared spectrum of O−3 and evidence for the stabilization of O2⋅⋅⋅O+4

Abstract

When a Ne:O3 sample is codeposited at approximately 5 K with neon atoms that have been excited in a microwave discharge, the most prominent infrared absorptions of the resulting solid are contributed by trans- and cyc-O+4 and by O−3. The failure to detect infrared absorptions of O+3 is consistent with the initial formation of that species in one or more dissociative excited states. The ν3 absorption of O−3 appears at 796.3 cm−1, close to its position in earlier argon-matrix experiments in which photoionization of an alkali metal atom provided the electron source and in which diffusion of the atomic cation would result in the stabilization of appreciable M+O−3. The identification of O−3 isolated in solid neon is supported by observations of O−3 generated from isotopically substituted Ne:O2:N2O samples, also codeposited with excited neon atoms. An upper bound of 810 cm−1 is estimated for the gas-phase band center of ν3 of O−3. Infrared absorptions which grow on mild warmup of the sample are tentatively assigned to an O2...O+4 complex.