title: Interstellar molecule CCCN may be formed by charge-stripping of [CCCN]- in the gas phase, and when energized, undergoes loss of C with partial carbon scrambling.
abstract: Deprotonation of CH2=CHCN with HO- in the chemical ionization source of a VG ZAB 2HF mass spectrometer gives CH2=-CCN which fragments through [H- (HCCCN)] to give [CCCN]-. Similar reactions with 13CH2CHCN and CH2CH13CN give [13CCCN]- and [CC13CN]-. Collision induced dissociations of these anions, together with calculations at the CCSD(T)/aug-cc-pVDZ//B3LYP/6-31+G(d) level of theory indicate that the anions do not rearrange under conditions used to charge strip them to their neutrals. A comparison of the charge reversal (-CR+) and neutralization/reionization (-NR+) mass spectra of [CCCN]- indicate that neutral C3N species (formed by charge stripping of the anion) decompose by loss of C. Experimental studies with the 13C labeled analogues indicate that the loss of C occurs subsequent to or accompanying partial carbon scrambling of the CCCN backbone. Theoretical studies suggest that this scrambling may occur during equilibration of CCCN and CCNC via a decomposing "rhombic" C3N intermediate.
authors.affiliation: Department of Chemistry, The University of Adelaide, South Australia, 5005.
authors.forename: Micheal J
authors.initials: MJ
authors.lastname: Maclean
authors.forename: Mark
authors.initials: M
authors.lastname: Fitzgerald
authors.forename: John H
authors.initials: JH
authors.lastname: Bowie