Magnetic Resonance Studies of Impurity-Helium Solids Containing Hydrogen and Deuterium Impurities

Impurity-Helium Solids (Im-He) produced by injecting a mixed beam of helium and impurity gases into superfluid ⁴He have been investigated by electron spin resonance (ESR) and nuclear magnetic resonance (NMR) techniques. NMR signals from deuterium molecules in a D₂-He solid have been studied. Only samples prepared from gaseous mixtures containing high concentrations of D₂ molecules gave observable signals. The ESR experiments were performed on H and/or D atomic impurities in Im-He solids containing H, D, H₂, and D₂ in various combinations. The exchange tunneling reactions D+H₂HD+H and D+HDD₂+H were used to generate high concentrations of H atoms (10¹⁷/cm³) in Im-He samples.