Laser photolysis of matrix-isolated methyl nitrate: Experimental and theoretical characterization of the infrared spectrum of imine peroxide (HNOO)

Photodissociation of methyl nitrate (and its fully deuterated isotopomer) i solated in an argon matrix at 17 K has been investigated by 266 nm laser ph otolysis. Characterization of the product species has been performed by tra nsmission Fourier transform infrared spectroscopy. There are two parallel i nitial reaction channels, one of which is formation of formaldehyde (H2CO) and hydrogen nitryl (HNO2). The second channel is formation of formaldehyde and a previously unreported species, imine peroxide (HNOO). Quantum chemic al calculations of the structure, vibrational frequencies, and infrared ban d intensities have been performed at the B3LYP/6-311++G**, MP2(full)/6-311+G**, and QCISD/6-311++** levels of theory. The calculated vibrational freq uency patterns allowed us to confirm the detection and infrared spectral as signments of imine peroxide for the first time.