Knowledge Bank

An FTIR study of the products of the vacuum uv photolysis of $CH3CCH$, methylacetylene and its partially and fully deuterated istopomers has revealed new information on the vibrational spectra of a variety of tricarbon hydride radicals, ). New vibrations for $C2H$, propynylidyne; $C3H2$, cis- and trans-propenediylidene, and $C3H3$, cyclopropenyl are proposed. Also observed are the cyclopropenylidene, vinylidenecarbene, and propargylene isomers of $C3H2$, and the $C3H3$, allyl radical. On the basis of isotopic data previous vibrational assignments are confirmed, and in some cases, revisions are suggested