title: Detection and Characterization of the Cumulene Carbenes H2C5 and H2C6
abstract: Two cumulene carbenes, H2C5 and H2C6, were detected in a supersonic molecular beam by Fourier transform microwave spectroscopy. Their rotational and leading centrifugal distortion constants were determined with high accuracy, such that the entire radio spectrum can now be calculated. Like the known carbenes H2C3 and H2C4, both molecules have singlet electronic ground states and linear carbon-chain backbones. They can be produced in sufficiently high concentrations in the laboratory that their electronic spectra, expected to lie in the visible, should be readily detectable by laser spectroscopy. The microwave spectra of other, more exotic isomers may be detectable as well.
authors.affiliation: M. C. McCarthy, M. J. Travers, P. Thaddeus, Division of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Cambridge, MA 02138, USA, and Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA. A. Kovacs and C. A. Gottlieb, Division of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Cambridge, MA 02138, USA. W. Chen and S. E. Novick, Department of Chemistry, Wesleyan University, Middletown, CT 06459, USA.
authors.initials: MC
authors.lastname: McCarthy
authors.initials: MJ
authors.lastname: Travers
authors.initials: A
authors.lastname: Kovacs
authors.initials: W
authors.lastname: Chen
authors.initials: SE
authors.lastname: Novick
authors.initials: CA
authors.lastname: Gottlieb
authors.initials: P
authors.lastname: Thaddeus