title: Is interstellar detection of higher members of the linear radicals CnCH and CnN feasible?
abstract: Rotational constants and dipole moments for linear-chain radicals CnCH and CnN are estimated using a combination of ab initio molecular orbital calculations and observed data on the starting members of the series.  CnCH with n = 0-5 have been observed by radioastronomy in carbon-rich interstellar clouds; higher members of the series have 2 pi ground states with large dipole moments and are strong candidates for observation.  CN and C3N have also been observed by radioastronomy; higher members of the series, with the possible exception of C5N, have 2 pi ground states with near-zero dipole moments making their interstellar detection hopeless under present observational conditions.  C5N can be a strong candidate only if it has a 2 sigma ground state, and our best computations so far indicate that this is not the case.
authors.affiliation: Molecular Research Institute, Palo Alto, USA.
authors.forename: F
authors.initials: F
authors.lastname: Pauzat
authors.forename: Y
authors.initials: Y
authors.lastname: Ellinger
authors.forename: A D
authors.initials: AD
authors.lastname: McLean
mesh_terms: D000114:Acetylene / Q000032:analysis / Q000737:chemistry; D055580:Astronomical Phenomena; D001256:Astronomy; D005118:Extraterrestrial Environment; D006838:Hydrocarbons / Q000032:analysis / Q000737:chemistry; D009584:Nitrogen / Q000032:analysis / Q000737:chemistry; D016082:Solar System
chemical_list: D006838:Hydrocarbons; D009584:Nitrogen; D000114:Acetylene