The vibrational spectra of molecular ions isolated in solid neon. V. N2O+ and NNO−2

Abstract

When a Ne:N2O=200 or 800 sample is codeposited at approximately 5 K with a beam of neon atoms that has been excited in a microwave discharge, the infrared spectrum of the products includes absorptions contributed by the two stretching fundamentals of ground-state N2O+. An absorption near 1200 cm−1 also results from the stabilization of NNO−2 on reaction of O− with N2O. The two other stretching fundamentals of NNO−2 have also been identified. Detailed isotopic substitution studies support these identifications and permit a normal coordinate analysis for both N2O+ and NNO−2. The nitrogen–nitrogen bond of NNO−2 has approximately single bond character, and the nitrogen–oxygen bonds are relatively weak. The photodestruction threshold for NNO−2 in this experimental system is near 420 nm. Photolysis of NNO−2 is accompanied by growth in the absorptions of cis ONNO. Several other infrared absorptions in the initial sample are tentatively assigned to vibrations of N2O complexed to various ions.