The infrared spectroscopy and photochemistry of NO3 trapped in solid neon

NO3 can be stabilized in solid neon either by codeposition at 4.3 K of a Ne:O-2 mixture with a Ne:NO mixture that has been passed through a microwave discharge or, in higher yield, by codeposition of a Ne:NO mixture with a Ne:O-2 mixture, followed by annealing of the deposit at similar to 7 K and exposure of the solid to near ultraviolet radiation. All of the previously reported bands of NO3 between 700 and 3000 cm(-1) were observed, most with neon-matrix shifts of less than 2.5 cm(-1). The infrared spectra of eight isotopic species of NO3 were obtained. The observed isotopic shifts demonstrate the occurrence of extensive mixing of ground-state levels of e(') symmetry and their strong vibronic interaction with the B E-2(') state. Photodissociation of NO3 by irradiation of the deposit at wavelengths longer than 520 nm leads to new absorptions near the fundamentals of NO and O-2 and other new absorptions at relatively low frequencies. These absorptions were depleted and NO3 regenerated by subsequent near ultraviolet irradiation of the deposit, suggesting the stabilization of a weakly bound NO(O-2) complex in solid neon.