title: An accurate molecular structure of phenyl, the simplest aryl radical.
abstract: The phenyl radical (C6H5(·)) is the prototypical σ-type aryl radical and one of the most common aromatic building blocks for larger ring molecules. Using a combination of rotational spectroscopy of singly substituted isotopic species and vibrational corrections calculated theoretically, an extremely accurate molecular structure has been determined. Relative to benzene, the phenyl radical has a substantially larger C-Cipso-C bond angle [125.8(3)° vs. 120°], and a shorter distance [2.713(3) Å vs. 2.783(2) Å] between the ipso and para carbon atoms.
authors.affiliation: Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (USA); Present address: Air Force Research Laboratory, Space Vehicles Directorate, Kirtland AFB, NM 87117 (USA).
authors.forename: Oscar
authors.initials: O
authors.lastname: Martinez
authors.forename: Kyle N
authors.initials: KN
authors.lastname: Crabtree
authors.forename: Carl A
authors.initials: CA
authors.lastname: Gottlieb
authors.forename: John F
authors.initials: JF
authors.lastname: Stanton
authors.forename: Michael C
authors.initials: MC
authors.lastname: McCarthy
keywords: ab initio calculations; molecular structure; rotational spectroscopy