Infrared spectra of matrix-isolated UO$sup +$$sub 2$ and NO$sup -$$sub 2$

The reactions of UO and UO$sub 2$ with NO and NO$sub 2$ have been studied by infrared spectroscopy using the matrix isolation technique. Codeposition of vaporized UO and UO$sub 2$ with NO$sub 2$ and with NO gases in an argon matrix at 14 K resulted in the production of the UO$sup +$$sub 2$ molecular ion paired with either a NO$sup -$$sub 2$ or NO$sup -$ anion. Three different reactions have been observed to yield a UO$sup +$$sub 2$ cation product: (1) UO$sub 2$+NO$sub 2$, (2) UO$sub 2$+NO, and (3) UO+NO$sub 2$. Infrared absorption frequencies in the range 1150--1190 cm$sup -1$ have been measured and interpreted as the stretching modes of bent (bond angle = 109degree) N$sup 16$O$sup -$$sub 2$, N$sup 16$O$sup 18$O$sup -$, and N$sup 18$O$sup -$$sub 2$ ions paired with UO$sup +$$sub 2$. Infrared absorption frequencies in the range 770--900 cm$sup - 1$ have been measured and interpreted as the stretching modes of linear U$sup 16$O$sup +$$sub 2$, U$sup 16$O$sup 18$O$sup +$, and U$sup 18$O$sup +$$sub 2$ paired with either NO$sup -$ or NO$sup -$$sub 2$. (AIP)