Photochemistry of tricarbonylnitrosylcobalt in frozen gas matrices at 20 K. Infrared spectroscopic evidence for dicarbonylnitrosylcobalt and dicarbonyl(dinitrogen)nitrosylcobalt

Abstract

Infrared evidence is presented for the formation of a three-co-ordinate species, [Co(CO)₂(NO)], on the u.v. photo-lysis of [Co(CO)₃(NO)] in argon and methane matrices.andfortheformationoffour-co-ordinatespecies. [Co(CO)₂( N₂)(NO)] and probably [Co(CO)(N₂)₂(NO)], in nitrogen matrices at 20 K. The primary photolysis steps are readily reversed by irradiation with visible light and by annealing the matrix in the case of the reaction of [Co(CO)₂(NO)] with CO. The results are discussed in relation to the postulate of co-ordinatively unsaturated and expanded-co-ordination-shell species as intermediates in the thermal substitution reactions of [Co(CO)₃(NO)].