′ ′ - X̃ 2 A 2 ′ Transition of NO 3 Trapped in Solid Neon †

NO3 has been stabilized in a neon matrix at 4.3 K in sufficient yield for detection of the absorptions between 7000 and 10 000 cm-1, which arise from vibronically allowed transitions from the ground state to levels of the à 2E′′ state. The results confirm and somewhat extend previous gas-phase observations for NO3. Additional spectra are presented for six other isotopologues of NO3, four of which possess C2V symmetry. The splitting patterns for these species support the previous assignments. Alternations in the spacings of the ν4 progression are consistent with the occurrence of weak to moderate Jahn-Teller interaction in the A 2E state of NO3.