title: Gas-phase structure determination of dihydroxycarbene, one of the smallest stable singlet carbenes.
abstract: Carbenes are reactive molecules of the form R(1)-:C-R(2) that play a role in topics ranging from organic synthesis to gas-phase oxidation chemistry. We report the first experimental structure determination of dihydroxycarbene (HO-:C-OH), one of the smallest stable singlet carbenes, using a combination of microwave rotational spectroscopy and high-level coupled-cluster calculations. The semi-experimental equilibrium structure derived from five isotopic variants of HO-:C-OH contains two very short CO single bonds (ca. 1.32 Å). Detection of HO-:C-OH in the gas phase firmly establishes that it is stable to isomerization, yet it has been underrepresented in discussions of the CH2O2 chemical system and its atmospherically relevant isomers: formic acid and the Criegee intermediate CH2OO.
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139 (USA).
authors.forename: Caroline C
authors.initials: CC
authors.lastname: Womack
authors.forename: Kyle N
authors.initials: KN
authors.lastname: Crabtree
authors.forename: Laura
authors.initials: L
authors.lastname: McCaslin
authors.forename: Oscar
authors.initials: O
authors.lastname: Martinez
authors.forename: Robert W
authors.initials: RW
authors.lastname: Field
authors.forename: John F
authors.initials: JF
authors.lastname: Stanton
authors.forename: Michael C
authors.initials: MC
authors.lastname: McCarthy
keywords: atmospheric chemistry; carbenes; microwave spectroscopy; reactive intermediates; structure elucidation