Triplet states of the amide group. Trapped electron spectra of formamide and related molecules

✍ Scribed by Ralph H. Staley; Lawrence B. Harding; W.A. Goddard III; J.L. Beauchamp

• Publisher: Elsevier Science
• Year: 1975
• Tongue: English
• Weight: 385 KB
• Volume: 36
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(75)85345-0

✦ Synopsis

Trapped electron (TE) spectra arc obtnincd using ion cyclotron rcsonancc dctcction of scavenged electrons. The lowest singlet-triplet trxWtions, 3(n-rr*)T in formamide (HCONH2) and N,N-dimcthyl formamidc (HCONhtc2) ax found at vertical energies of 5.30 and 5.00 cV, respcctivcly. An unresolved band containing the 3(n* n*) and 3(n+ 3s) statcs appears al higher energies, ccntcred at 6.60 arid 6.00 cV, respcctivcly. The TE spectra of formaldehyde (HCHO), acctaldehyde (M&HO) and acctonc (hlczC0) arc obtained for comparison ar.d arc used alcn, m with results from ab initio !hcoretical calculations in establishing assigmenls. Singlet-triplet transitions dominate the spectra of all of thcsc carbonyl containing mokcuks, to the csclusioil of l&v lying singlet-singlet transitions.

This is in agrccmcnt with other T'E spccrra arxl the espectatjon that (do/dE) will be higher near threshold for singlet-triplei as compared to sin:ler-sinplct transitions.