Pulsed-NMR study of the long-range order in solid H2 and D2

Quadrature Fourier transform NMR detection has been employed to study the disorder-order transition in high J=1 concentration solid hydrogen and deuterium. In solid H2, where the ortho-para conversion is rapid, quick measurements were made possible by computer batch files containing pulse programs. Newly obtained order parameters were compared with those from the so-called quadrupole glass phase. In addition, peculiar emission of power was detected and regarded as characteristic of the long-range order which distinguishes it from the local order in the quadrupole glass phase.