Enclosed are trajectories and input files produced using i-Pi v2.0.0 and Quantum Espresso v6.1 (along with KGEC for Kubo-Greenwood conductivity calculations) used in the following publication:
Van De Bund, Sebastiaan, Heather Wiebe, and Graeme J. Ackland. "Isotope quantum effects in the metallization transition in liquid hydrogen." Physical Review Letters (2021).
Further details on these data can be found therein.
Calculations can be redone using the provided i-Pi input files and modifying the initialization to include the inital positions, as obtained from the centroid trajectory. To reproduce runs, the pseudo-random number generator seed in the i-Pi input file must stay the same to ensure correct velocity initialization. Similarly, Quantum Espresso can be initialized using template input files provided with the appropriate starting position. See i-Pi/Quantum Espresso manuals for instructions on how to set up and run Quantum Espresso as a client for i-Pi.
Note that we employ the Baldereschi point throughout the calculations for Brillouin zone sampling, except for the Kubo-Greenwood calculations which uses the Chadi-Cohen generalization of this to yied 4 points instead. This can be done by using the following set of k-points in Quantum Espresso:
K_POINTS (tpiba)
4
0.125 0.125 0.125 0.125
0.375 0.125 0.125 0.375
0.375 0.375 0.125 0.375
0.375 0.375 0.375 0.125
The contents of the folders are as follows:
-- "main_traj": Extensive BLYP runs equilibrated in NPT and with production runs in NVT (PIMD for both H2/D2, along with additional classical nuclei MD for H2 only) including centroid/bead trajectories, and thermodynamic properties (including pressure and volume for EOS). Folders are labelled by temperature and pressure.
-- "other_xc": Additional runs using PBE and vdw-DF functionals for both H2/D2, using NPT only.
-- "kg_cond": Kubo-Greenwood conductivity calculations using slices of main trajectory data (for PIMD/BLYP runs only for both H2/D2). Folder names in each pressure and temperature run correspond to the slice index of the centroid trajectory found in the "main_traj" folder.
-- "suppl": Supplementary data: DOS calculations using slices of main trajectory data in a similar format to conductivity calculations.
-- "sample_inputs" Contains example input files showing the parameters used for Quantum Espresso. "dos" contains scf and nscf input files for DOS calculations, "kg_cond" contains scf input files for Kubo-Greenwood calculations, and "molecular dynamics" contains scf input files for all other calculations ("main_traj" and "extra_xc").