This file describes the contents of the tarballs and lists
compatible version of the software they relate to.
DFT.tar.bz2 (in dft.zip)
===========
This tarball contains files from the DFT calculations in which:
- the primitive cell was relaxed at a fixed external pressure
within DFT,
- the supercell lattice vectors were chosen so as to minimize the
finite size errors in the subsequent QMC calculations, and
- the k-vector offset at which to perform QMC wave function
optimization was chosen.
The tarball consists of a root diretory named DFT, containing
subdirectories named //. The DFT directory
contains the following files:
- ///*.supercell:
Summary of the resulting supercell parameters in human-readable
form. The supercell lattice vectors and supercell matrix were
determined from the primitive lattice vectors using the
'supercell' CASINO utility.
- ///Offsets/hydrogen.cell
///Offsets/hydrogen.param
Base CASTEP input files used for the determination of the optimal
k-offset.
- ///Offsets/kvectors.txt
Human-readable summary of the process of determining the optimal
twist angle for the QMC wave function optimization stage. In
this process we evaluated the DFT energies obtained with a
k-point grid commensurate with the supercell offset by each of
the 8 inequivalent twist angles which result in a real-valued
wave function, compared them with the DFT energy obtained
using a fine k-point grid, and we picked the twist angle which
minimized this difference. The twist angles and energies are
listed in the file.
- ///Calcs/hydrogen.cell
///Calcs/hydrogen.param
CASTEP input files used for the generation of the plane-wave
orbitals for QMC runs.
Not included in this tarball are the CASTEP *recpot files which are
part of CASTEP, CASTEP output files which were dynamically handled
and whose results are summarized instead, and resulting DFT orbital
files used in the QMC runs due to size considerations.
VMC.tar.bz2 (in vmc.zip)
===========
This tarball contains files from the VMC wave function optimization
runs which determined the Jastrow factor and backflow parameters used
in the subsequent DMC calculations.
The tarball consists of a root diretory named VMC, containing
subdirectories named //. The VMC directory
contains the following files:
- ///sj/input
///sj/cdata.0
Base CASINO input file for the optimization of an SJ wave
function, and initial correlation.data parameter file
representing an "empty" Jastrow correlation factor.
- ///sj/out.1
///sj/cdata.1
CASINO output file for an optimization run consisting of two
cycles of mean-absolute-deviation-from-the-median minimization
(MADmin) with cut-off lengths held fixed, and resulting
correlation.data parameter file after this stage.
- ///sj/out.2
///sj/cdata.2
CASINO output file for an optimization run consisting of one
MADmin cycle with cut-off lengths allowed to vary, and resulting
correlation.data parameter file after this stage.
- ///sj/out.3
///sj/cdata.3
///sj/correlation.data
CASINO output file for an optimization run consisting of one
energy minimization (Emin) cycle with cut-off lengths held fixed,
and resulting correlation.data parameter file after this stage.
- ///bf/input
///bf/cdata.0
///bf/out.1
///bf/cdata.1
///bf/out.2
///bf/cdata.2
///bf/out.3
///bf/cdata.3
///bf/correlation.data
(For N=96 only) Analogous to the above; CASINO input, output and
parameter files for the optimization of an SJB wave function
starting from the optimized SJ wave function. The three
optimization stages are:
- 1 MADmin cycle with cut-off lengths held fixed
- 2 MADmin cycles with cut-off lengths allowed to vary
- 1 Emin cycle with cut-off lengths held fixed
- /results.txt
Human-readable summary of optimization results and basic quality
checks.
Not included in this tarball are the DFT orbital files, due to
size considerations.
DMC.tar.bz2 (in dmc.zip)
===========
This tarball contains files from the twist-averaged DMC runs and
finite-size correction calculations from which our final results
were drawn.
The tarball consists of a root diretory named DMC, containing
subdirectories named //. The DMC directory
contains the following files:
- ///twist*/SJDMC_dt/input
///twist**/SJDMC_dt/correlation.data
///twist**/SJDMC_dt/out*
Base CASINO input file, wave-function parameter file, and
per-stage output files for the **th twist of the twist-averaged
DMC calculation with timestep .
- ///twist**/SJDMC_dt/reblock.results
Human-readable summary of the statistical reblocking analysis
performed on the DMC data for each twist and timestep, containing
the data used in our final results.
- ///twist**/SJDMC_dt/finsize.log
(N=768 only.) Human-readable summary of the evaluation of the
contribution of the twists to the finite size correction to the
exchange-correlation energy, computed from the static structure
factor evaluated during the DMC calculation.
- ///twist**/SJDMC_dt**/TWIST_IGNORED_FOR_XC_CORRECTION_DUE_TO_TRUNCATED_FILE
(N=768 only.) Empty file to flag absence of finsize.log for a
given twist, which is ignored in the XC correction for technical
reasons.
- ///twist**/E_SJDMC_dt0.dat
Human-readable text file containing the zero-timestep
extrapolation of the DMC energy and its errorbar for each twist.
- ///twist**/hydrogen.castep
CASTEP output files detailing the generation of the DFT orbitals
for use in DMC and the evaluation of the DFT energy at the given
twist using the PBE functional.
- ///twist**/hydrogen_kzk.castep
CASTEP output files detailing the evaluation of the DFT energy at
the given twist using the KZK functional.
- ///twistav_fit.results
Human readable summary of the fit performed to obtain the
twist-averaged DMC energy.
- ///PBE_fine/hydrogen.cell
///PBE_fine/hydrogen.param
///PBE_fine/hydrogen.castep
///LDA_fine/hydrogen.cell
///LDA_fine/hydrogen.param
///LDA_fine/hydrogen.castep
///KZK_fine/hydrogen.cell
///KZK_fine/hydrogen.param
///KZK_fine/hydrogen.castep
CASTEP input and output files for DFT using fine k-point grids
with the PBE, LDA and KZK functionals.
- ///PBE_twistinfo/hydrogen.cell
///PBE_twistinfo/hydrogen.param
///PBE_twistinfo/STATUS
///KZK_twistinfo/hydrogen.cell
///KZK_twistinfo/hydrogen.param
///KZK_twistinfo/STATUS
CASTEP input files and log of process of generation of DFT
orbitals and evaluation of the DFT energy at the different
twists using the PBE and KZK functionals; the CASTEP output
files corresponding to these DFT runs are the hydrogen.castep
and hydrogen_kzk.castep files detailed above.
- ///KE_corr/hydrogen.cell
///KE_corr/hydrogen.param
///KE_corr/hydrogen.castep
(N=768 only.) CASTEP input and output files correspoding to
the generation of DFT orbitals for the QMC evaluation of the
finite size correction to the kinetic energy.
- ///KE_corr/input
///KE_corr/correlation.data
///KE_corr/out
(N=768 only.) CASINO input, wave function parameter and output
files for the QMC evaluation of the finite size correction to the
kinetic energy.
- ///E_SJDMC_dt0_v_twist.dat
Text file with lines of the format:
where is the "naive" DMC statistical error, and
also accounts for the error due to the random
sampling of k-space.
- ///E_SJDMC_dt0_twistav.dat
///E_SJDMC_dt0_twistav_kerror.dat
///E_SJDMC_dt0_KZKcorr.dat
///E_SJDMC_dt0_KZKcorr_kerror.dat
Text files giving final results, namely the twist averaged DMC
energy and error bar, the twist averaged DMC energy and error bar
including k-sampling random error, the KZK-corrected
twist-averaged DMC energy and error bar, and the KZK-corrected
twist-averaged DMC energy, respectively.
- //E_SJDMC_dt0_KZKcorr_v_V.dat
//E_SJDMC_dt0_KZKcorr_v_V_kerror.dat
//E_SJDMC_dt0_twistav_v_V.dat
//E_SJDMC_dt0_twistav_v_V_kerror.dat
Text files plotting the respective results (as described above)
against volume.
- //virial_p_v_V.dat
Text file plotting the pressure derived from the above data and
the virial theorem, including error bar, against volume.
- //ke_corr_v_V.dat
//xc_corr_v_V.dat
(N=768 only.) Finite size corrections to the kinetic and
exchange-correlation energies, respectively, plotted as a
function of volume. The XC correction plot includes statistical
error bars.
For the select cases where backflow DMC calculations were
performed, files named like their Slater-Jastrow counterparts
replacing "SJDMC" with "SJBDMC" contain the relevant results.
Not included in the tarball are the CASTEP *recpot files which are
part of CASTEP, the DFT orbital files, and the CASINO output files
containing the raw DMC local energies and expectation values, due to
size considerations, and summaries are given instead.
Anharmonic.tar.bz2 (in anharmonic.zip)
==================
This tarball countains files from the DFT-based evaluation of the
anharmonic vibrational corrections used in our final results.
The tarball consists of a root directory named Anharmonic,
containing subdirectories with raw data. The Anharmonic directory
contains the following files:
- BO_energy_surfaces/_.dat
Born-Oppenheimer energy surfaces calculated using CASTEP, used
as input for the CAESAR anharmonic corrections research code.
Each file contains one data block for each symmetry-inequivalent
mode in the crystal, where the first line gives the harmonic
frequency of the mode (a.u.) and each subsequent line gives the
amplitude of the mode (a.u.) and the corresponding DFT energy
(eV).
- anharmonic_corrections.dat
Final anharmonic corrections (eV/atom) vs pressure (GPa) obtained
from the CAESAR anharmonic corrections research code.
Not included in this tarball are the CASTEP input and output files,
which were generated dynamically.
Software versions
=================
- CASTEP files are compatible with CASTEP version 6.11 and later.
For information on how to get a copy of CASTEP visit:
http://www.castep.org
- CASINO files are compatible with CASINO version 2.12 and later.
For information on how to get a copy of CASINO visit:
http://vallico.net/casinoqmc/
- For information on the CAESAR anharmonic corrections research code
email bm418 at cam.ac.uk.
*