ESR observation of the Hâ â â H, Hâ â â D, and Dâ â â D spin-pair radicals in rare gas matrices
Knight, L. B.; Rice, W. E.; Moore, L.; Davidson, E. R. ESR observation of the Hâ â â H, Hâ â â D, and Dâ â â D spin-pair radicals in rare gas matrices. J. Chem. Phys. 1995, 103, 5275-5275.
The first experimental observation of the fundamentally important spinâ€pair radicals, H...H, H...D, and D...D is reported. ESR(electron spin resonance) studies of rare gas matrices near 4 K containing extremely high concentrations of H and D atoms revealed the presence of these spin exchangeâ€coupled molecules whose ESRspectra are analyzed in terms of a 3Î£ electronic ground state. The observed Dtensor (zeroâ€field splitting) for a specific isotopic spin pair was surprisingly constant in all four rare gases but showed large changes among the three isotopic species. As expected, the hyperfine splitting (A iso) for the spinâ€pair was observed to be oneâ€half that of the free H or D atom.
Journal of Chemical Physics