TRANSLATIONAL AND ROTATIONAL SPECTRA IN THE FUNDAMENTAL INFRARED BAND OF LIQUID AND SOLID PARAHYDROGEN

The Q1(0) and Q1(0)+S0(0) infrared bands have been studied in liquid and solid para-H-2 with particular regard to their translational sidebands. In the liquid, their line shapes are well fitted by a model in which the excited particle is encapsulated. In the solid, the phonon sidebands reproduce the main features of the density of states (DOS), as extracted from neutron scattering. The S1(0)+S0(0) band shows a pure rotonic line shape which is well described by recent DOS calculations.