title: Electron spin resonance investigation of H2(+), HD(+), and D2(+) isolated in neon matrices at 2 K.
abstract: Various isotopologues of nature's simplest molecule, namely H(2)(+), HD(+), and D(2)(+), have been isolated in neon matrices at 2 K for the first time and studied by electron spin resonance (ESR). Over many years, hundreds of matrix isolation experiments employing a variety of deposition conditions and ion generation methods have been tried to trap the H(2)(+) cation radical in our laboratory. The molecule has been well characterized in the gas phase and by theoretical methods. The observed magnetic parameters for H(2)(+) in neon at 2 K are: g(∥) ≈ g(⊥) = 2.0022(1); A(iso)(H) = 881(7) MHz; and A(dip)(H) = 33(3) MHz. Reasonable agreement with gas phase values of the isotropic hyperfine interaction (A(iso)) is observed; however, the neon matrix dipolar hyperfine interaction (A(dip)) is noticeably below the gas phase value. The smaller matrix value of A(dip) is attributable to motional averaging of the H(2)(+) radical in the neon matrix trapping site--an occurrence that would prevent the full extent of the hyperfine anisotropy from being measured for a powder pattern type ESR sample.
authors.affiliation: Department of Chemistry, Furman University, 3300 Poinsett Hwy, Greenville, South Carolina 29613, USA.
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Correnti
authors.forename: Kyle P
authors.initials: KP
authors.lastname: Dickert
authors.forename: Mark A
authors.initials: MA
authors.lastname: Pittman
authors.forename: John W
authors.initials: JW
authors.lastname: Felmly
authors.forename: John J
authors.initials: JJ
authors.lastname: Banisaukas
authors.forename: Lon B
authors.initials: LB
authors.lastname: Knight