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Title: AB INITIO CHARACTERIZATION OF C{sup -}{sub 4}, C{sub 4}H, AND C{sub 4}H{sup -}

Journal Article · · Astrophysical Journal
 [1];  [2]
  1. Departamento de AstrofIsica Molecular e Infrarroja (DAMIR), IEM-CSIC, C/Serrano 121. 28006 Madrid (Spain)
  2. Universite Paris Est, Laboratoire de Modelisation et Simulation Multi Echelle, FRE3160 CNRS, Champs sur Marne, F-77454 Marne-la Vallee, Cedex 2 (France)

Using state-of-the-art theoretical methods, we investigate the stable isomers of C{sup -}{sub 4}, C{sub 4}H and C{sub 4}H{sup -}. Three of them are relevant for astrophysics and astrochemistry. These computations are performed using highly correlated ab initio methods and the aug-cc-pVXZ (X = T,Q) basis sets. In addition to the linear isomers, we predict the existence of several cyclic and branched forms for these molecules. For all the molecular species of interest here, sets of spectroscopic parameters are determined with perturbation theory, which compare quite well with experiment. For l - C{sub 4}H{sup -}(X {sup 1}SIGMA{sup +}), the quartic force field is computed at the coupled cluster level of theory. This force field is derived from full nine-dimensional potential energy surface generated close to the equilibrium geometry of this anion. Finally, we treat the thermochemistry of the hydrogen attachment and the electron attachment reactions that may lead to the formation of the C{sub 4}H{sup -} from either C{sup -}{sub 4} or C{sub 4}H.

OSTI ID:
21392380
Journal Information:
Astrophysical Journal, Vol. 708, Issue 2; Other Information: DOI: 10.1088/0004-637X/708/2/1452; ISSN 0004-637X
Country of Publication:
United States
Language:
English