Electron spin resonance investigation of H2+, HD+, and D2+ isolated in neon matrices at 2 K
Correnti, M. D.; Dickert, K. P.; Pittman, M. A.; Felmly, J. W.; Banisaukas, J. J.; Knight, L. B. Electron spin resonance investigation of H2+, HD+, and D2+ isolated in neon matrices at 2 K. J. Chem. Phys. 2012, 137, 204308-204308.
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(-ˆ¥) -‰ˆ g(-Š¥) = 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.
Journal of Chemical Physics