Coll, Cornelius FHarris, A. BrooksBerlinsky, A. John2023-05-232023-05-231970-09-282015-08-11https://repository.upenn.edu/handle/20.500.14332/43022The anharmonic interactions between librational waves in solid hydrogen are found to lead to significant perturbations in the single-libron spectrum. This large anharmonicity is also responsible for two-libron processes whose frequencies and Raman intensities are calculated. Our results for the one- and two-libron spectra are in excellent agreement with, and hence explain, the optical data.PhysicsQuantum PhysicsArticle