Shifts in the ESR Spectral Parameters of Atomic Hydrogen and Deuterium in Frozen Acids

Publisher Website
Google Scholar
Abstract
The ESR spectra of atomic hydrogen and deuterium trapped in frozen acids has been reinvestigated in an effort to determine whether systematic shifts in the spectral parameters exist for this neutral S‐state atom. Following the example of Livingston, Zeldes, and Taylor, partially deuterated perchloric, phosphoric, and sulfuric acids were studied after γ irradiation at 77°K. Breit—Rabi expressions which take account of the nuclear quadrupole coupling energy were used in treating the data. This study discloses g‐value shifts of −0.00019, −0.00016, and −0.00012 and relative A‐value shifts of −0.94%, −0.61%, and −0.38% from the free‐gas values for the three acids, respectively. For perchloric and sulfuric acids, nuclear quadrupole coupling energies of 0.18 and 0.13 Mc/sec, respectively, were obtained. The possibility of 1s and 3dz2 mixing in the hydrogen‐atom ground term due to crystalline electric fields is discussed.