title: Structure and Electronic Transitions of C7H4O2+and C7H5O2+Ions: Neon Matrix and Theoretical Studies.
abstract: C7H4O2+and C7H5O2+ions and the respective neutrals have been investigated by absorption spectroscopy in neon matrixes following mass selection of ions produced from salicylic acid. Three electronic transitions starting at 649.6, 431.0, and 372.0 nm are detected for C7H4O2+and assigned on the basis of CASPT2 energies and Franck-Condon simulations as the excitations from the X2A″ to the 12A″, 22A″, and 32A″ electronic states of 6-(oxomethylene)-2,4-cyclohexadien-1-one ion (A+). Absorptions commencing at 366.4 nm are observed for C7H5O2+and assigned to the 12A' ← X2A' electronic transition of (2-hydroxyphenyl)methanone ion (J+). Neutralization of J+leads to the appearance of four absorption systems attributed to the 42A″, 32A″, 22A″, and 12A″ ← X2A″ transitions of J with origin bands 291.3, 361.2, 393.8, and 461.2 nm.
authors.affiliation: Department of Chemistry, University of Basel , Klingelbergstrasse 80, CH-4056, Basel, Switzerland.|Institute of Physics, Polish Academy of Sciences , Al. Lotników, 32/46, PL-02-668 Warsaw, Poland.
authors.forename: Jan
authors.identifier: http://orcid.org/0000-0003-1325-0079
authors.initials: J
authors.lastname: Fulara
authors.affiliation: Department of Chemistry, University of Basel , Klingelbergstrasse 80, CH-4056, Basel, Switzerland.
authors.forename: Sonia
authors.initials: S
authors.lastname: Erattupuzha
authors.affiliation: Department of Chemistry, University of Basel , Klingelbergstrasse 80, CH-4056, Basel, Switzerland.
authors.forename: Iryna
authors.initials: I
authors.lastname: Garkusha
authors.affiliation: Department of Chemistry, University of Basel , Klingelbergstrasse 80, CH-4056, Basel, Switzerland.
authors.forename: John P
authors.identifier: http://orcid.org/0000-0001-8878-8573
authors.initials: JP
authors.lastname: Maier