ROLE OF THE CAGE DIMER OF FORMALDEHYDE IN THE PHOTOLYSIS OF FORMALDEHYDE - ARGON MATRIX AT 12-K

Photolysis of H2CO was carried out in an Ar matrix with different matrix ratios (M/R). The infrared (IR) absorption spectra of the initial matrix preparation show that the matrix isolated monomers are almost exclusively present at very high dilutions (M/R or 5000) whereas the cage dimers and higher multimers are present in significant amounts at lower dilutions. The post-photolysis IR spectra indicate that the photodecomposition of H2CO is mainly effected with the cage dimer, and that CH3OH and CO are formed as photoproducts. The majority of the photoproducts exist as cage dimers of CH3OH/CO. Upon thermal annealing after photolysis, diffusion through the matrix leads to the additional formation of aggregates composed of CH3OH/H2CO as well as CH3OH/CO. © 1979.