Phonons in metallic hydrogen

This contains the inputs necessary to reproduce the RQMC band structures in our paper. One starts by calculating the forces on the atoms when they are all randomly displaced (force_calculations). The resultant forces and displacements are then assembled into a linear regression, subject to the crystal symmetries, to calculate force constants and subsequent phonon properties (phonon_calculations). The pseudopotentials used are provided in pseudo, and the primitive cells for the final structures used are provided in structure; for the supercells, see input files for the calculations.