Input data format: { } = optional, [ ] = it depends, | = or
All quantities whose dimensions are not explicitly specified are in
HARTREE ATOMIC UNITS. Charge is "number" charge (i.e. not multiplied
by e); potentials are in energy units (i.e. they are multiplied by e)
BEWARE: TABS, CRLF, ANY OTHER STRANGE CHARACTER, ARE A SOURCES OF TROUBLE
USE ONLY PLAIN ASCII TEXT FILES (CHECK THE FILE TYPE WITH UNIX COMMAND "file")
Namelists must appear in the order given below.
Comment lines in namelists can be introduced by a "!", exactly as in
fortran code. Comments lines in ``cards'' can be introduced by
either a "!" or a "#" character in the first position of a line.
Do not start any line in ``cards'' with a "/" character.
Leave a space between card names and card options, e.g.
ATOMIC_POSITIONS (bohr), not ATOMIC_POSITIONS(bohr)
Structure of the input data:
===============================================================================
&CONTROL
...
/
&SYSTEM
...
/
&ELECTRONS
...
/
[ &IONS
...
/ ]
[ &CELL
...
/ ]
[ &WANNIER
...
/ ]
ATOMIC_SPECIES
X Mass_X PseudoPot_X
Y Mass_Y PseudoPot_Y
Z Mass_Z PseudoPot_Z
ATOMIC_POSITIONS { alat | bohr | crystal | angstrom }
X 0.0 0.0 0.0 {if_pos(1) if_pos(2) if_pos(3)}
Y 0.5 0.0 0.0
Z O.0 0.2 0.2
[ CELL_PARAMETERS { alat | bohr | angstrom }
v1(1) v1(2) v1(3)
v2(1) v2(2) v2(3)
v3(1) v3(2) v3(3) ]
[ OCCUPATIONS
f_inp1(1) f_inp1(2) f_inp1(3) ... f_inp1(10)
f_inp1(11) f_inp1(12) ... f_inp1(nbnd)
[ f_inp2(1) f_inp2(2) f_inp2(3) ... f_inp2(10)
f_inp2(11) f_inp2(12) ... f_inp2(nbnd) ] ]
[ CONSTRAINTS
nconstr { constr_tol }
constr_type(.) constr(1,.) constr(2,.) [ constr(3,.) constr(4,.) ] { constr_target(.) } ]
[ ATOMIC_FORCES
label_1 Fx(1) Fy(1) Fz(1)
.....
label_n Fx(n) Fy(n) Fz(n) ]
'cp'
a string describing the task to be performed:
'cp',
'scf',
'nscf',
'relax',
'vc-relax',
'vc-cp',
'cp-wf',
'vc-cp-wf'
(vc = variable-cell).
(wf = Wannier functions).
'MD Simulation '
reprinted on output.
'low'
In order of decreasing verbose output:
'debug' | 'high' | 'medium' | 'low','default' | 'minimal'
ndr
ndw
100
Number of steps between successive savings of
information needed to restart the run.
'restart'
'from_scratch' : from scratch
'restart' : from previous interrupted run
'reset_counters' : continue a previous simulation,
performs "nstep" new steps, resetting
the counter and averages
number of Car-Parrinello steps performed in this run
50
10
Number of steps between successive writings of relevant physical quantities
to files named as "prefix.???" depending on "prefix" parameter.
In the standard output relevant quantities are written every 10*iprint steps.
.false.
Write stress tensor to standard output each "iprint" steps.
It is set to .TRUE. automatically if calculation='vc-relax'
.false.
print forces. Set to .TRUE. when ions are moving.
1.D0
time step for molecular dynamics, in Hartree atomic units
(1 a.u.=2.4189 * 10^-17 s : beware, PW code use
Rydberg atomic units, twice that much!!!)
value of the ESPRESSO_TMPDIR environment variable if set;
current directory ('./') otherwise
input, temporary, trajectories and output files are found
in this directory.
This flag controls the saving of charge density in CP codes:
If .TRUE. save charge density to restart dir,
If .FALSE. do not save charge density.
'cp'
prepended to input/output filenames and restart folders:
prefix.pos : atomic positions
prefix.vel : atomic velocities
prefix.for : atomic forces
prefix.cel : cell parameters
prefix.str : stress tensors
prefix.evp : energies
prefix.hrs : Hirshfeld effective volumes (ts-vdw)
prefix.eig : eigen values
prefix.nos : Nose-Hoover variables
prefix.spr : spread of Wannier orbitals
prefix.wfc : center of Wannier orbitals
prefix.ncg : number of Poisson CG steps (PBE0)
prefix_ndw.save/ : write restart folder
prefix_ndr.save/ : read restart folder
where ndr and ndw are the integers number described below
50
The restart files are read from the folder
outdir/prefix_ndr.save/
where outdir, prefix and ndr are the input variables described
in this document
50
The restart files are written, if ndw > 0, in the folder
outdir/prefix_ndw.save/
where outdir, prefix and ndw are the input variables described
in this document
.false.
.true. to compute the volume and/or the surface of an isolated
system for finite pressure/finite surface tension calculations
(PRL 94, 145501 (2005); JCP 124, 074103 (2006)).
1.D+7, or 150 days, i.e. no time limit
jobs stops after max_seconds CPU time. Used to prevent
a hard kill from the queuing system.
1.0D-4
convergence threshold on total energy (a.u) for ionic
minimization: the convergence criterion is satisfied
when the total energy changes less than etot_conv_thr
between two consecutive scf steps.
See also forc_conv_thr - both criteria must be satisfied
1.0D-3
convergence threshold on forces (a.u) for ionic
minimization: the convergence criterion is satisfied
when all components of all forces are smaller than
forc_conv_thr.
See also etot_conv_thr - both criteria must be satisfied
1.0D-6
convergence criterion for electron minimization:
convergence is achieved when "ekin < ekin_conv_thr".
See also etot_conv_thr - both criteria must be satisfied.
'default'
'high': CP code will write Kohn-Sham wfc files and additional
information in data-file.xml in order to restart
with a PW calculation or to use postprocessing tools.
If disk_io is not set to 'high', the data file
written by CP will not be readable by PW or PostProc.
'default'
'small': NO LONGER IMPLEMENTED SINCE v.6.3
memory-saving tricks are implemented. Currently:
- the G-vectors are sorted only locally, not globally
- they are not collected and written to file
For large systems, the memory and time gain is sizable
but the resulting data files are not portable - use it
only if you do not need to re-read the data file
value of the $ESPRESSO_PSEUDO environment variable if set;
'$HOME/espresso/pseudo/' otherwise
directory containing pseudopotential files
.FALSE.
If .TRUE. a homogeneous finite electric field described
through the modern theory of the polarization is applied.
REQUIRED
Bravais-lattice index. If ibrav /= 0, specify EITHER
[ celldm(1)-celldm(6) ] OR [ A,B,C,cosAB,cosAC,cosBC ]
but NOT both. The lattice parameter "alat" is set to
alat = celldm(1) (in a.u.) or alat = A (in Angstrom);
see below for the other parameters.
For ibrav=0 specify the lattice vectors in CELL_PARAMETER,
optionally the lattice parameter alat = celldm(1) (in a.u.)
or = A (in Angstrom), or else it is taken from CELL_PARAMETERS
ibrav structure celldm(2)-celldm(6)
or: b,c,cosbc,cosac,cosab
0 free
crystal axis provided in input: see card CELL_PARAMETERS
1 cubic P (sc)
v1 = a(1,0,0), v2 = a(0,1,0), v3 = a(0,0,1)
2 cubic F (fcc)
v1 = (a/2)(-1,0,1), v2 = (a/2)(0,1,1), v3 = (a/2)(-1,1,0)
3 cubic I (bcc)
v1 = (a/2)(1,1,1), v2 = (a/2)(-1,1,1), v3 = (a/2)(-1,-1,1)
-3 cubic I (bcc), more symmetric axis:
v1 = (a/2)(-1,1,1), v2 = (a/2)(1,-1,1), v3 = (a/2)(1,1,-1)
4 Hexagonal and Trigonal P celldm(3)=c/a
v1 = a(1,0,0), v2 = a(-1/2,sqrt(3)/2,0), v3 = a(0,0,c/a)
5 Trigonal R, 3fold axis c celldm(4)=cos(gamma)
The crystallographic vectors form a three-fold star around
the z-axis, the primitive cell is a simple rhombohedron:
v1 = a(tx,-ty,tz), v2 = a(0,2ty,tz), v3 = a(-tx,-ty,tz)
where c=cos(gamma) is the cosine of the angle gamma between
any pair of crystallographic vectors, tx, ty, tz are:
tx=sqrt((1-c)/2), ty=sqrt((1-c)/6), tz=sqrt((1+2c)/3)
-5 Trigonal R, 3fold axis <111> celldm(4)=cos(gamma)
The crystallographic vectors form a three-fold star around
<111>. Defining a' = a/sqrt(3) :
v1 = a' (u,v,v), v2 = a' (v,u,v), v3 = a' (v,v,u)
where u and v are defined as
u = tz - 2*sqrt(2)*ty, v = tz + sqrt(2)*ty
and tx, ty, tz as for case ibrav=5
Note: if you prefer x,y,z as axis in the cubic limit,
set u = tz + 2*sqrt(2)*ty, v = tz - sqrt(2)*ty
See also the note in Modules/latgen.f90
6 Tetragonal P (st) celldm(3)=c/a
v1 = a(1,0,0), v2 = a(0,1,0), v3 = a(0,0,c/a)
7 Tetragonal I (bct) celldm(3)=c/a
v1=(a/2)(1,-1,c/a), v2=(a/2)(1,1,c/a), v3=(a/2)(-1,-1,c/a)
8 Orthorhombic P celldm(2)=b/a
celldm(3)=c/a
v1 = (a,0,0), v2 = (0,b,0), v3 = (0,0,c)
9 Orthorhombic base-centered(bco) celldm(2)=b/a
celldm(3)=c/a
v1 = (a/2, b/2,0), v2 = (-a/2,b/2,0), v3 = (0,0,c)
-9 as 9, alternate description
v1 = (a/2,-b/2,0), v2 = (a/2, b/2,0), v3 = (0,0,c)
10 Orthorhombic face-centered celldm(2)=b/a
celldm(3)=c/a
v1 = (a/2,0,c/2), v2 = (a/2,b/2,0), v3 = (0,b/2,c/2)
11 Orthorhombic body-centered celldm(2)=b/a
celldm(3)=c/a
v1=(a/2,b/2,c/2), v2=(-a/2,b/2,c/2), v3=(-a/2,-b/2,c/2)
12 Monoclinic P, unique axis c celldm(2)=b/a
celldm(3)=c/a,
celldm(4)=cos(ab)
v1=(a,0,0), v2=(b*cos(gamma),b*sin(gamma),0), v3 = (0,0,c)
where gamma is the angle between axis a and b.
-12 Monoclinic P, unique axis b celldm(2)=b/a
celldm(3)=c/a,
celldm(5)=cos(ac)
v1 = (a,0,0), v2 = (0,b,0), v3 = (c*cos(beta),0,c*sin(beta))
where beta is the angle between axis a and c
13 Monoclinic base-centered celldm(2)=b/a
celldm(3)=c/a,
celldm(4)=cos(gamma)
v1 = ( a/2, 0, -c/2),
v2 = (b*cos(gamma), b*sin(gamma), 0 ),
v3 = ( a/2, 0, c/2),
where gamma=angle between axis a and b projected on xy plane
-13 Monoclinic base-centered celldm(2)=b/a
(unique axis b) celldm(3)=c/a,
celldm(5)=cos(beta)
v1 = ( a/2, b/2, 0),
v2 = ( -a/2, b/2, 0),
v3 = (c*cos(beta), 0, c*sin(beta)),
where beta=angle between axis a and c projected on xz plane
IMPORTANT NOTICE: until QE v.6.4.1, axis for ibrav=-13 had a
different definition: v1(old) = v2(now), v2(old) = -v1(now)
14 Triclinic celldm(2)= b/a,
celldm(3)= c/a,
celldm(4)= cos(bc),
celldm(5)= cos(ac),
celldm(6)= cos(ab)
v1 = (a, 0, 0),
v2 = (b*cos(gamma), b*sin(gamma), 0)
v3 = (c*cos(beta), c*(cos(alpha)-cos(beta)cos(gamma))/sin(gamma),
c*sqrt( 1 + 2*cos(alpha)cos(beta)cos(gamma)
- cos(alpha)^2-cos(beta)^2-cos(gamma)^2 )/sin(gamma) )
where alpha is the angle between axis b and c
beta is the angle between axis a and c
gamma is the angle between axis a and b
ibrav
Crystallographic constants - see the "ibrav" variable.
Specify either these OR A,B,C,cosAB,cosBC,cosAC NOT both.
Only needed values (depending on "ibrav") must be specified
alat = celldm(1) is the lattice parameter "a" (in BOHR)
If ibrav=0, only celldm(1) is used if present;
cell vectors are read from card CELL_PARAMETERS
Traditional crystallographic constants: a,b,c in ANGSTROM
cosAB = cosine of the angle between axis a and b (gamma)
cosAC = cosine of the angle between axis a and c (beta)
cosBC = cosine of the angle between axis b and c (alpha)
The axis are chosen according to the value of "ibrav".
Specify either these OR "celldm" but NOT both.
Only needed values (depending on "ibrav") must be specified
The lattice parameter alat = A (in ANGSTROM )
If ibrav = 0, only A is used if present;
cell vectors are read from card CELL_PARAMETERS
REQUIRED
number of atoms in the unit cell
REQUIRED
number of types of atoms in the unit cell
for an insulator, nbnd = number of valence bands
(nbnd = # of electrons /2);
for a metal, 20% more (minimum 4 more)
number of electronic states (bands) to be calculated.
Note that in spin-polarized calculations the number of
k-point, not the number of bands per k-point, is doubled
0.0
total charge of the system. Useful for simulations with charged cells.
By default the unit cell is assumed to be neutral (tot_charge=0).
tot_charge=+1 means one electron missing from the system,
tot_charge=-1 means one additional electron, and so on.
In a periodic calculation a compensating jellium background is
inserted to remove divergences if the cell is not neutral.
-1 [unspecified]
total majority spin charge - minority spin charge.
Used to impose a specific total electronic magnetization.
If unspecified, the tot_magnetization variable is ignored
and the electronic magnetization is determined by the
occupation numbers (see card OCCUPATIONS) read from input.
REQUIRED
kinetic energy cutoff (Ry) for wavefunctions
4 * ecutwfc
kinetic energy cutoff (Ry) for charge density and potential
For norm-conserving pseudopotential you should stick to the
default value, you can reduce it by a little but it will
introduce noise especially on forces and stress.
If there are ultrasoft PP, a larger value than the default is
often desirable (ecutrho = 8 to 12 times ecutwfc, typically).
PAW datasets can often be used at 4*ecutwfc, but it depends
on the shape of augmentation charge: testing is mandatory.
The use of gradient-corrected functional, especially in cells
with vacuum, or for pseudopotential without non-linear core
correction, usually requires an higher values of ecutrho
to be accurately converged.
ecutrho
three-dimensional FFT mesh (hard grid) for charge
density (and scf potential). If not specified
the grid is calculated based on the cutoff for
charge density.
three-dimensional mesh for wavefunction FFT and for the smooth
part of charge density ( smooth grid ).
Coincides with nr1, nr2, nr3 if ecutrho = 4 * ecutwfc ( default )
dimensions of the "box" grid for Ultrasoft pseudopotentials
must be specified if Ultrasoft PP are present
a string describing the occupation of the electronic states.
Allowed values are 'fixed' (default) and 'ensemble'.
In the case of conjugate gradient style of minimization
of the electronic states, if occupations is set to 'ensemble',
this allows ensemble DFT calculations for metallic systems.
0.D0 Ha
parameter for the smearing function, only used for ensemble DFT
calculations. Hartree atomic units
a string describing the kind of occupations for electronic states
in the case of ensemble DFT (occupations == 'ensemble' );
possible values are: 'gaussian', 'fermi-dirac', 'hermite-delta',
'gaussian-splines', 'cold-smearing', 'marzari-vanderbilt', '0', '-1'.
Warning: only 'gaussian' is tested.
1
nspin = 1 : non-polarized calculation (default)
nspin = 2 : spin-polarized calculation, LSDA
(magnetization along z axis)
0.0
q2sigma
0.0
q2sigma
0.1
ecfixed, qcutz, q2sigma: parameters for modified functional to be
used in variable-cell molecular dynamics (or in stress calculation).
"ecfixed" is the value (in Rydberg) of the constant-cutoff;
"qcutz" and "q2sigma" are the height and the width (in Rydberg)
of the energy step for reciprocal vectors whose square modulus
is greater than "ecfixed". In the kinetic energy, G^2 is
replaced by G^2 + qcutz * (1 + erf ( (G^2 - ecfixed)/q2sigma) )
See: M. Bernasconi et al, J. Phys. Chem. Solids 56, 501 (1995)
read from pseudopotential files
Exchange-correlation functional: eg 'PBE', 'BLYP' etc
See Modules/funct.f90 for allowed values.
Overrides the value read from pseudopotential files.
Use with care and if you know what you are doing!
Use 'PBE0' to perform hybrid functional calculation using Wannier functions.
Allowed calculation: 'cp-wf' and 'vc-cp-wf'
See CP specific user manual for further guidance (or in CPV/Doc/user_guide.tex)
and examples in CPV/examples/EXX-wf-example.
Also see related keywords starting with exx_.
it depends on the specified functional
Fraction of EXX for hybrid functional calculations. In the case of
input_dft='PBE0', the default value is 0.25. This entry overrides
the default (as well as the restart file) value of a given functional.
.FALSE.
lda_plus_u = .TRUE. enables calculation with LDA+U
("rotationally invariant"). See also Hubbard_U.
Anisimov, Zaanen, and Andersen, PRB 44, 943 (1991);
Anisimov et al., PRB 48, 16929 (1993);
Liechtenstein, Anisimov, and Zaanen, PRB 52, R5467 (1994);
Cococcioni and de Gironcoli, PRB 71, 035105 (2005).
0.D0 for all species
LDA+U works only for a few selected elements. Modify
CPV/ldaU.f90 if you plan to use LDA+U with an
element that is not configured there.
Hubbard_U(i): parameter U (in eV) for LDA+U calculations.
Currently only the simpler, one-parameter LDA+U is
implemented (no "alpha" or "J" terms)
'none'
Type of Van der Waals correction. Allowed values:
'grimme-d2', 'Grimme-D2', 'DFT-D', 'dft-d': semiempirical Grimme's DFT-D2.
Optional variables: "london_s6", "london_rcut"
S. Grimme, J. Comp. Chem. 27, 1787 (2006),
V. Barone et al., J. Comp. Chem. 30, 934 (2009).
'TS', 'ts', 'ts-vdw', 'ts-vdW', 'tkatchenko-scheffler': Tkatchenko-Scheffler
dispersion corrections with first-principle derived C6 coefficients
Optional variables: "ts_vdw_econv_thr", "ts_vdw_isolated"
See A. Tkatchenko and M. Scheffler, Phys. Rev. Lett. 102, 073005 (2009)
J. Hermann et al., J. Chem. Phys. 159, 174802 (2023), doi:10.1063/5.0170972
'XDM', 'xdm': Exchange-hole dipole-moment model. Optional variables: "xdm_a1", "xdm_a2"
(implemented in PW only)
A. D. Becke and E. R. Johnson, J. Chem. Phys. 127, 154108 (2007)
A. Otero de la Roza, E. R. Johnson, J. Chem. Phys. 136, 174109 (2012)
Note that non-local functionals (eg vdw-DF) are NOT specified here but in "input_dft"
0.75
global scaling parameter for DFT-D. Default is good for PBE.
200
cutoff radius (a.u.) for dispersion interactions
.FALSE.
OBSOLESCENT, same as vdw_corr='TS'
1.D-6
Optional: controls the convergence of the vdW energy (and forces). The default value
is a safe choice, likely too safe, but you do not gain much in increasing it
.FALSE.
Optional: set it to .TRUE. when computing the Tkatchenko-Scheffler vdW energy
for an isolated (non-periodic) system.
'none'
Used to perform calculation assuming the system to be
isolated (a molecule of a clustr in a 3D supercell).
Currently available choices:
'none' (default): regular periodic calculation w/o any correction.
'makov-payne', 'm-p', 'mp' : the Makov-Payne correction to the
total energy is computed.
Theory:
G.Makov, and M.C.Payne,
"Periodic boundary conditions in ab initio
calculations" , Phys.Rev.B 51, 4014 (1995)
var nextffield -type INTEGER {
default { 0 }
info {
Number of activated external ionic force fields.
See Doc/ExternalForceFields.tex for further explanation and parameterizations
}
}
100
maximum number of iterations in a scf step
'none'
set how electrons should be moved
'none' : electronic degrees of freedom (d.o.f.) are kept fixed
'sd' : steepest descent algorithm is used to minimize
electronic d.o.f.
'damp' : damped dynamics is used to propagate electronic d.o.f.
'verlet' : standard Verlet algorithm is used to propagate
electronic d.o.f.
'cg' : conjugate gradient is used to converge the
wavefunction at each ionic step. 'cg' can be used
interchangeably with 'verlet' for a couple of ionic
steps in order to "cool down" the electrons and
return them back to the Born-Oppenheimer surface.
Then 'verlet' can be restarted again. This procedure
is useful when electronic adiabaticity in CP is lost
yet the ionic velocities need to be preserved.
1.D-6
Convergence threshold for selfconsistency:
estimated energy error < conv_thr
20
frequency in iterations for which the conjugate-gradient algorithm
for electronic relaxation is restarted
0.D0
Amplitude of the finite electric field (in a.u.;
1 a.u. = 51.4220632*10^10 V/m). Used only if tefield=.TRUE.
3
direction of the finite electric field (only if tefield == .TRUE.)
In the case of a PARALLEL calculation only the case epol==3
is implemented
400.D0
effective electron mass in the CP Lagrangian, in atomic units
( 1 a.u. of mass = 1/1822.9 a.m.u. = 9.10939 * 10^-31 kg )
2.5D0
mass cut-off (in Rydberg) for the Fourier acceleration
effective mass is rescaled for "G" vector components with
kinetic energy above "emass_cutoff"
'ortho'
selects the orthonormalization method for electronic wave
functions
'ortho' : use iterative algorithm - if it doesn't converge,
reduce the timestep, or use options ortho_max
and ortho_eps, or use Gram-Schmidt instead just
to start the simulation
'Gram-Schmidt' : use Gram-Schmidt algorithm - to be used ONLY in
the first few steps.
YIELDS INCORRECT ENERGIES AND EIGENVALUES.
1.D-8
tolerance for iterative orthonormalization
meaningful only if orthogonalization = 'ortho'
300
maximum number of iterations for orthonormalization
meaningful only if orthogonalization = 'ortho'
0
OBSOLETE: use command-line option " -nd XX" instead
0.1D0
damping frequency times delta t, optimal values could be
calculated with the formula :
SQRT( 0.5 * LOG( ( E1 - E2 ) / ( E2 - E3 ) ) )
where E1, E2, E3 are successive values of the DFT total energy
in a steepest descent simulations.
meaningful only if " electron_dynamics = 'damp' "
'zero' : restart setting electronic velocities to zero
'default' : restart using electronic velocities of the
previous run
'change_step' : restart simulation using electronic velocities of the
previous run, with rescaling due to the timestep change.
specify the old step via tolp as in
tolp = 'old_time_step_value' in au.
Note that you may want to specify
ion_velocities = 'change_step'
'not_controlled'
'nose' : control electronic temperature using Nose
thermostat. See also "fnosee" and "ekincw".
'rescaling' : control electronic temperature via velocities
rescaling.
'not_controlled' : electronic temperature is not controlled.
0.001D0
value of the average kinetic energy (in atomic units) forced
by the temperature control
meaningful only with " electron_temperature /= 'not_controlled' "
1.D0
oscillation frequency of the nose thermostat (in terahertz)
meaningful only with " electron_temperature = 'nose' "
'random'
'atomic': start from superposition of atomic orbitals
(not yet implemented)
'random': start from random wfcs. See "ampre".
.FALSE.
if .TRUE. perform a conjugate gradient minimization of the
electronic states for every ionic step.
It requires Gram-Schmidt orthogonalization of the electronic
states.
100
maximum number of conjugate gradient iterations for
conjugate gradient minimizations of electronic states
0.3D0
small step used in the conjugate gradient minimization
of the electronic states.
.FALSE.
if .TRUE. perform the precondition of the CG gradient
using the kinetic energy of the state.
2
number of internal cycles for every conjugate gradient
iteration only for ensemble DFT
1
frequency in iterations at which a full inner cycle, only
for cold smearing, is performed
0.03D0
step for inner cycle with cold smearing, used when a not full
cycle is performed
1.D0
a number <= 1, very close to 1: the damping in electronic
damped dynamics is multiplied at each time step by "grease"
(avoids overdamping close to convergence: Obsolete ?)
grease = 1 : normal damped dynamics
0.D0
amplitude of the randomization ( allowed values: 0.0 - 1.0 )
meaningful only if " startingwfc = 'random' "
Specify the type of ionic dynamics.
For constrained dynamics or constrained optimisations add the
CONSTRAINTS card (when the card is present the SHAKE algorithm is
automatically used).
'none' : ions are kept fixed
'sd' : steepest descent algorithm is used to minimize ionic
configuration
'cg' : conjugate gradient algorithm is used to minimize ionic
configuration
'damp' : damped dynamics is used to propagate ions
'verlet' : standard Verlet algorithm is used to propagate ions
'default'
'default ' : if restarting, use atomic positions read from the
restart file; in all other cases, use atomic
positions from standard input.
'from_input' : restart the simulation with atomic positions read
from standard input, even if restarting.
'default'
tempw
initial ionic velocities
'default' : restart the simulation with atomic velocities read
from the restart file
'change_step' : restart the simulation with atomic velocities read
from the restart file, with rescaling due to the
timestep change, specify the old step via tolp
as in tolp = 'old_time_step_value' in au.
Note that you may want to specify
electron_velocities = 'change_step'
'random' : start the simulation with random atomic velocities
(see also variable tempw)
'from_input' : restart the simulation with atomic velocities read
from standard input - see card 'ATOMIC_VELOCITIES'
BEWARE: tested only with electrons_dynamics='cg'
'zero' : restart the simulation with atomic velocities set
to zero
0.2D0
damping frequency times delta t, optimal values could be
calculated with the formula :
SQRT( 0.5 * LOG( ( E1 - E2 ) / ( E2 - E3 ) ) )
where E1, E2, E3 are successive values of the DFT total energy
in a steepest descent simulations.
meaningful only if " ion_dynamics = 'damp' "
0.5 a.u. for all species
ion_radius(i): pseudo-atomic radius of the i-th atomic species
used in Ewald summation. Typical values: between 0.5 and 2.
Results should NOT depend upon such parameters if their values
are properly chosen. See also "iesr".
1
The real-space contribution to the Ewald summation is performed
on iesr*iesr*iesr cells. Typically iesr=1 is sufficient to have
converged results.
1
number of electronic steps per ionic step.
.FALSE.
This keyword is useful when simulating the dynamics and/or the
thermodynamics of an isolated system. If set to true the total
torque of the internal forces is set to zero by adding new forces
that compensate the spurious interaction with the periodic
images. This allows for the use of smaller supercells.
BEWARE: since the potential energy is no longer consistent with
the forces (it still contains the spurious interaction with the
repeated images), the total energy is not conserved anymore.
However the dynamical and thermodynamical properties should be
in closer agreement with those of an isolated system.
Also the final energy of a structural relaxation will be higher,
but the relaxation itself should be faster.
'not_controlled'
'nose' : control ionic temperature using Nose-Hoover
thermostat see parameters "fnosep", "tempw",
"nhpcl", "ndega", "nhptyp"
'rescaling' : control ionic temperature via velocities
rescaling. see parameter "tolp"
'not_controlled' : ionic temperature is not controlled
300.D0
value of the ionic temperature (in Kelvin) forced by the
temperature control.
meaningful only with " ion_temperature /= 'not_controlled' "
or when the initial velocities are set to 'random'
"ndega" controls number of degrees of freedom used in
temperature calculation
1.D0
oscillation frequency of the nose thermostat (in terahertz)
[note that 3 terahertz = 100 cm^-1]
meaningful only with " ion_temperature = 'nose' "
for Nose-Hoover chain one can set frequencies of all thermostats
( fnosep = X Y Z etc. ) If only first is set, the defaults for
the others will be same.
100.D0
tolerance (in Kelvin) of the rescaling. When ionic temperature
differs from "tempw" more than "tolp" apply rescaling.
meaningful only with ion_temperature = 'rescaling'
or with ion_velocities='change_step', where it specifies
the old timestep
1
number of thermostats in the Nose-Hoover chain
currently maximum allowed is 4
0
type of the "massive" Nose-Hoover chain thermostat
nhptyp=1 uses a NH chain per each atomic type
nhptyp=2 uses a NH chain per atom, this one is useful
for extremely rapid equipartitioning (equilibration is a
different beast)
nhptyp=3 together with nhgrp allows fine grained thermostat
control
NOTE: if using more than 1 thermostat per system there will
be a common thermostat added on top of them all, to disable
this common thermostat specify nhptyp=-X instead of nhptyp=X
0
specifies which thermostat group to use for given atomic type
when >0 assigns all the atoms in this type to thermostat
labeled nhgrp(i), when =0 each atom in the type gets its own
thermostat. Finally, when <0, then this atomic type will have
temperature "not controlled". Example: HCOOLi, with types H (1), C(2), O(3), Li(4);
setting nhgrp={2 2 0 -1} will add a common thermostat for both H & C,
one thermostat per each O (2 in total), and a non-updated thermostat
for Li which will effectively make temperature for Li "not controlled"
(Nat_{total}-1)/Nat_{total}
these are the scaling factors to be used together with nhptyp=3 and nhgrp(i)
in order to take care of possible reduction in the degrees of freedom due to
constraints. Suppose that with the previous example HCOOLi, C-H bond is
constrained. Then, these 2 atoms will have 5 degrees of freedom in total instead
of 6, and one can set fnhscl={5/6 5/6 1. 1.}. This way the target kinetic energy
for H&C will become 6(kT/2)*5/6 = 5(kT/2). This option is to be used for
simulations with many constraints, such as rigid water with something else in there
0
number of degrees of freedom used for temperature calculation
ndega <= 0 sets the number of degrees of freedom to
[3*nat-abs(ndega)], ndega > 0 is used as the target number
amprp
.false.
If .TRUE. randomize ionic positions for the
atomic type corresponding to the index.
amprp
0.D0
amplitude of the randomization for the atomic type corresponding
to the index i ( allowed values: 0.0 - 1.0 ).
meaningful only if " tranp(i) = .TRUE.".
1.D0
same as "grease", for ionic damped dynamics.
'default' : restart the simulation with cell parameters read
from the restart file or "celldm" if
"restart = 'from_scratch'"
'from_input' : restart the simulation with cell parameters
from standard input.
( see the card 'CELL_PARAMETERS' )
'pr' if calculation = 'vc-md', 'vc'cp', 'vc-cp-wf';
'damp-pr' if calculation = 'vc-relax';
'none' otherwise
set how cell should be moved
'none' : cell is kept fixed
'sd' : steepest descent algorithm is used to optimise the
cell
'damp-pr' : damped dynamics is used to optimise the cell
( Parrinello-Rahman method ).
'pr' : standard Verlet algorithm is used to propagate
the cell ( Parrinello-Rahman method ).
'zero' : restart setting cell velocity to zero
'default' : restart using cell velocity of the previous run
0.1D0
damping frequency times delta t, optimal values could be
calculated with the formula :
SQRT( 0.5 * LOG( ( E1 - E2 ) / ( E2 - E3 ) ) )
where E1, E2, E3 are successive values of the DFT total energy
in a steepest descent simulations.
meaningful only if " cell_dynamics = 'damp' "
0.D0
Target pressure [KBar] in a variable-cell md or relaxation run.
0.75*Tot_Mass/pi**2 for Parrinello-Rahman MD;
0.75*Tot_Mass/pi**2/Omega**(2/3) for Wentzcovitch MD
Fictitious cell mass [amu] for variable-cell simulations
(both 'vc-md' and 'vc-relax')
1.2D0
Used in the construction of the pseudopotential tables.
It should exceed the maximum linear contraction of the
cell during a simulation.
'not_controlled'
'nose' : control cell temperature using Nose thermostat
see parameters "fnoseh" and "temph".
'rescaling' : control cell temperature via velocities
rescaling.
'not_controlled' : cell temperature is not controlled.
0.D0
value of the cell temperature (in ???) forced
by the temperature control.
meaningful only with " cell_temperature /= 'not_controlled' "
1.D0
oscillation frequency of the nose thermostat (in terahertz)
meaningful only with " cell_temperature = 'nose' "
1.D0
same as "grease", for cell damped dynamics
'all'
Select which of the cell parameters should be moved:
all = all axis and angles are moved
x = only the x component of axis 1 (v1_x) is moved
y = only the y component of axis 2 (v2_y) is moved
z = only the z component of axis 3 (v3_z) is moved
xy = only v1_x and v2_y are moved
xz = only v1_x and v3_z are moved
yz = only v2_y and v3_z are moved
xyz = only v1_x, v2_y, v3_z are moved
shape = all axis and angles, keeping the volume fixed
2Dxy = only x and y components are allowed to change
2Dshape = as above, keeping the area in xy plane fixed
volume = isotropic variations of v1_x, v2_y, v3_z, keeping
the shape fixed. Should be used only with ibrav=1.
.false.
.true. for finite pressure calculations
.false.
.true. for finite surface tension calculations
0.D0
external pressure in GPa
.false.
.true. for variable pressure calculations
pressure changes linearly with time:
Delta_P = (P_fin - P_in)/nstep
0.D0
only if pvar = .true.
initial value of the external pressure (GPa)
0.D0
only if pvar = .true.
final value of the external pressure (GPa)
0.D0
Surface tension (in a.u.; typical values 1.d-4 - 1.d-3)
0.D0
threshold parameter which defines the electronic charge density
isosurface to compute the 'quantum' volume of the system
(typical values: 1.d-4 - 1.d-3)
(corresponds to alpha in PRL 94 145501 (2005))
0.D0
thikness of the external skin of the electronic charge density
used to compute the 'quantum' surface
(typical values: 1.d-4 - 1.d-3; 50% to 100% of rho_thr)
(corresponds to Delta in PRL 94 145501 (2005))
Output files used by Wannier Function options are the following
fort.21: Used only when calwf=5, contains the full list of g-vecs.
fort.22: Used Only when calwf=5, contains the coeffs. corresponding
to the g-vectors in fort.21
fort.24: Used with calwf=3,contains the average spread
fort.25: Used with calwf=3, contains the individual Wannier
Function Spread of each state
fort.26: Used with calwf=3, contains the wannier centers along a
trajectory.
fort.27: Used with calwf=3 and 4, contains some general runtime
information from ddyn, the subroutine that actually
does the localization of the orbitals.
fort.28: Used only if efield=.TRUE. , contains the polarization
contribution to the total energy.
Also, The center of mass is fixed during the Molecular Dynamics.
BEWARE : THIS WILL ONLY WORK IF THE NUMBER OF PROCESSORS IS LESS THAN OR
EQUAL TO THE NUMBER OF STATES.
Nota Bene 1: For calwf = 5, wffort is not used. The
Wannier/Wave(function) coefficients are written to unit 22
and the corresponding g-vectors (basis vectors) are
written to unit 21. This option gives the g-vecs and
their coeffs. in reciprocal space, and the coeffs. are
complex. You will have to convert them to real space
if you want to plot them for visualization. calwf=1 gives
the orbital densities in real space, and this is usually
good enough for visualization.
.false.
If dynamics will be done in the presence of a field
.false.
Whether to turn on the field adiabatically (adiabatic switch)
if true, then nbeg is set to 0.
1
No. of iterations over which the field will be turned on
to its final value. Starting value is 0.0
If sw_len < 0, then it is set to 1.
If you want to just optimize structures on the presence of a
field, then you may set this to 1 and run a regular geometry
optimization.
0.D0
Initial values of the field along x, y, and z directions
0.D0
Final values of the field along x, y, and z directions
1
Localization algorithm for Wannier function calculation:
wfsd=1 Damped Dynamics
wfsd=2 Steepest-Descent / Conjugate-Gradient
wfsd=3 Jocobi Rotation
Remember, this is consistent with all the calwf options
as well as the tolw (see below).
Not a good idea to Wannier dynamics with this if you are
using restart='from_scratch' option, since the spreads
converge fast in the beginning and ortho goes bananas.
5.D0
The minimum step size to take in the SD/CG direction
0.3D0
The maximum step size to take in the SD/CG direction
The code calculates an optimum step size, but that may be
either too small (takes forever to converge) or too large
(code goes crazy) . This option keeps the step size between
wfdt and maxwfdt. In my experience 0.1 and 0.5 work quite
well. (but don't blame me if it doesn't work for you)
10
Number of iterations to do for Wannier convergence.
10
Out of a total of NIT iterations, NSD will be Steepest-Descent
and ( nit - nsd ) will be Conjugate-Gradient.
1500.D0
Fictitious mass of the A matrix used for obtaining
maximally localized Wannier functions. The unitary
transformation matrix U is written as exp(A) where
A is a anti-hermitian matrix. The Damped-Dynamics is performed
in terms of the A matrix, and then U is computed from A.
Usually a value between 1500 and 2500 works fine, but should
be tested.
0.3D0
Damping coefficient for Damped-Dynamics.
20
Number of Damped-Dynamics steps to be performed per CP
iteration.
1.D-8
Convergence criterion for localization.
.true.
Whether to adapt the damping parameter dynamically.
3
Wannier Function Options, can be 1,2,3,4,5
1. Output the Wannier function density, nwf and wffort
are used for this option. see below.
2. Output the Overlap matrix O_i,j=<w_i|exp{iGr}|w_j>. O is
written to unit 38. For details on how O is constructed,
see below.
3. Perform nsteps of Wannier dynamics per CP iteration, the
orbitals are now Wannier Functions, not Kohn-Sham orbitals.
This is a Unitary transformation of the occupied subspace
and does not leave the CP Lagrangian invariant. Expectation
values remain the same. So you will **NOT** have a constant
of motion during the run. Don't freak out, its normal.
4. This option starts for the KS states and does 1 CP iteration
and nsteps of Damped-Dynamics to generate maximally
localized wannier functions. Its useful when you have the
converged KS groundstate and want to get to the converged
Wannier function groundstate in 1 CP Iteration.
5. This option is similar to calwf 1, except that the output is
the Wannier function/wavefunction, and not the orbital
density. See nwf below.
0
This option is used with calwf 1 and calwf 5. with calwf=1,
it tells the code how many Orbital densities are to be
output. With calwf=5, set this to 1(i.e calwf=5 only writes
one state during one run. so if you want 10 states, you have
to run the code 10 times). With calwf=1, you can print many
orbital densities in a single run.
See also the PLOT_WANNIER card for specifying the states to
be printed.
40
This tells the code where to dump the orbital densities. Used
only with CALWF=1. for e.g. if you want to print 2 orbital
densities, set calwf=1, nwf=2 and wffort to an appropriate
number (e.g. 40) then the first orbital density will be
output to fort.40, the second to fort.41 and so on. Note that
in the current implementation, the following units are used
21,22,24,25,26,27,28,38,39,77,78 and whatever you define as
ndr and ndw. so use number other than these.
.false.
Output the charge density (g-space) and the list of g-vectors
This is useful if you want to reconstruct the electrostatic
potential using the Poisson equation. If .TRUE. then the
code will output the g-space charge density and the list
if G-vectors, and STOP.
Charge density is written to : CH_DEN_G_PARA.ispin (1 or 2
depending on the number of spin types) or CH_DEN_G_SERL.ispin
depending on if the code is being run in parallel or serial
G-vectors are written to G_PARA or G_SERL.
60
An initial guess on the maximum number of neighboring (overlapping) MLWFs.
8.0
Radial cutoff distance (in bohr) for including overlapping MLWF pairs
in EXX calculations.
See J. Chem. Theory Comput. 16, 3757–3785 (2020).
1.0D-6
Poisson solver convergence criterion during computation of the EXX potential.
.false.
Use cubic instead of spherical subdomains as local supports during computation
of the EXX potential. If set to .TRUE., the spherical domain
radii (exx_ps_rcut_self, exx_ps_rcut_pair, exx_me_rcut_self, exx_me_rcut_pair)
will be treated as half of the side length of the cubic subdomain.
6.0
Radial cutoff distance (in bohr) to compute the self EXX energy.
This distance determines the radius of the Poisson sphere centered at
a given MLWF center, and should be large enough to cover
the majority of the MLWF charge density.
See J. Chem. Theory Comput. 16, 3757–3785 (2020).
exx_use_cube_domain
5.0
Radial cutoff distance (in bohr) to compute the pair EXX energy.
This distance determines the radius of the Poisson sphere centered at
the midpoint of two overlapping MLWFs, and should be
large enough to cover the majority of the MLWF product density.
This parameter can generally be chosen as smaller than exx_ps_rcut_self.
See J. Chem. Theory Comput. 16, 3757–3785 (2020).
exx_use_cube_domain
10.0
Radial cutoff distance (in bohr) for the multipole-expansion sphere
centered at a given MLWF center.
The far-field self EXX potential in this sphere is generated with a
multipole expansion of the MLWF charge density.
This parameter must be larger than exx_ps_rcut_self by at least 3
real-space grid point spacings.
See J. Chem. Theory Comput. 16, 3757–3785 (2020).
exx_use_cube_domain
7.0
Radial cutoff distance (in bohr) for the multipole-expansion sphere
centered at the midpoint of two overlapping MLWFs.
The far-field pair EXX potential in this sphere is generated with
a multipole expansion of the MLWF product density.
This parameter must be larger than exx_ps_rcut_pair by at least 3
real-space grid point spacings. Also, this parameter can generally
be chosen as smaller than exx_me_rcut_self.
See J. Chem. Theory Comput. 16, 3757–3785 (2020).
exx_use_cube_domain
label of the atom. Acceptable syntax:
chemical symbol X (1 or 2 characters, case-insensitive)
or chemical symbol plus a number or a letter, as in
"Xn" (e.g. Fe1) or "X_*" or "X-*" (e.g. C1, C_h;
max total length cannot exceed 3 characters)
mass of the atomic species [amu: mass of C = 12]
not used if calculation='scf', 'nscf', 'bands'
File containing PP for this species.
The pseudopotential file is assumed to be in the new UPF format.
If it doesn't work, the pseudopotential format is determined by
the file name:
*.vdb or *.van Vanderbilt US pseudopotential code
*.RRKJ3 Andrea Dal Corso's code (old format)
none of the above old PWscf norm-conserving format
alat | bohr | angstrom | crystal
(DEPRECATED) bohr
alat : atomic positions are in cartesian coordinates,
in units of the lattice parameter (either
celldm(1) or A).
bohr : atomic positions are in cartesian coordinate,
in atomic units (i.e. Bohr).
If no option is specified, 'bohr' is assumed;
not specifying units is DEPRECATED and will no
longer be allowed in the future
angstrom: atomic positions are in cartesian coordinates,
in Angstrom
crystal : atomic positions are in crystal coordinates, i.e.
in relative coordinates of the primitive lattice
vectors as defined either in card CELL_PARAMETERS
or via the ibrav + celldm / a,b,c... variables
Specified atomic positions will be IGNORED and those from the
previous scf calculation will be used instead !!!
label of the atom as specified in ATOMIC_SPECIES
atomic positions
component i of the force for this atom is multiplied by if_pos(i),
which must be either 0 or 1. Used to keep selected atoms and/or
selected components fixed in MD dynamics or
structural optimization run.
1
when starting with ion_velocities = "from_input" it is convenient
to perform a few steps (~5-10) with a small time step (0.5 a.u.).
The velocities must be expressed using the same length units
indicated in the card ATOMIC_POSITIONS, divided by time
in atomic units.
label of the atom as specified in ATOMIC_SPECIES
atomic velocities along x,y and z direction
bohr | angstrom | alat
'bohr'/'angstrom': lattice vectors in bohr radii / angstrom.
'alat' / nothing specified: lattice vectors in units or the
lattice parameter (either celldm(1) or a). Not specifing
units is DEPRECATED and will not be allowed in the future.
If nothing specified and no lattice parameter specified,
'bohr' is assumed - DEPRECATED, will no longer be allowed
bohr | angstrom
bohr / angstrom: reference cell parameters in bohr radii / angstrom.
To mimic a constant effective planewave kinetic energy (ecfixed) during a
variable-cell calculation, the specified reference cell has to be large enough
such that the individual cell vector lengths of the fluctuating cell do not
exceed the corresponding reference lattice vector lengths during the entire
calculation. The cost of the calculation will increase with the increasing
size of the reference cell. The user must test for the proper reference cell
parameters.
The reference cell parameters should be used in conjunction with q2sigma,
qcutz, and ecfixed. See q2sigma for more information about mimicking constant
effective planewave kinetic energy (ecfixed) during variable-cell calculations.
The reference cell parameters should be chosen as an isotropic scaling of the
initial cell of the system. This means that the reference cell should have
the same shape as the initial simulatoin cell. The reference cell parameters should
NOT be changed throughout a given simulatoin. Typically, 2%-10% scaling of
the unit cell vectors are sufficient. However, the cell fluctuations depend on
the system and the thermodynamic conditions. So again user must test for the proper
choice of reference cell parameters.
When this card is present the SHAKE algorithm is automatically used.
Number of constraints.
Tolerance for keeping the constraints satisfied.
Type of constrain :
'type_coord' : constraint on global coordination-number, i.e. the
average number of atoms of type B surrounding the
atoms of type A. The coordination is defined by
using a Fermi-Dirac.
(four indexes must be specified).
'atom_coord' : constraint on local coordination-number, i.e. the
average number of atoms of type A surrounding a
specific atom. The coordination is defined by
using a Fermi-Dirac.
(four indexes must be specified).
'distance' : constraint on interatomic distance
(two atom indexes must be specified).
'planar_angle' : constraint on planar angle
(three atom indexes must be specified).
'torsional_angle' : constraint on torsional angle
(four atom indexes must be specified).
'bennett_proj' : constraint on the projection onto a given direction
of the vector defined by the position of one atom
minus the center of mass of the others.
( Ch.H. Bennett in Diffusion in Solids, Recent
Developments, Ed. by A.S. Nowick and J.J. Burton,
New York 1975 ).
These variables have different meanings
for different constraint types:
'type_coord' : constr(1) is the first index of the
atomic type involved
constr(2) is the second index of the
atomic type involved
constr(3) is the cut-off radius for
estimating the coordination
constr(4) is a smoothing parameter
'atom_coord' : constr(1) is the atom index of the
atom with constrained coordination
constr(2) is the index of the atomic
type involved in the coordination
constr(3) is the cut-off radius for
estimating the coordination
constr(4) is a smoothing parameter
'distance' : atoms indices object of the
constraint, as they appear in
the 'ATOMIC_POSITION' CARD
'planar_angle', 'torsional_angle' : atoms indices object of the
constraint, as they appear in the
'ATOMIC_POSITION' CARD (beware the
order)
'bennett_proj' : constr(1) is the index of the atom
whose position is constrained.
constr(2:4) are the three coordinates
of the vector that specifies the
constraint direction.
Target for the constrain ( angles are specified in degrees ).
This variable is optional.
Occupations of individual states (MAX 10 PER LINE).
For spin-polarized calculations, these are majority spin states.
Occupations of minority spin states (MAX 10 PER LINE)
To be specified only for spin-polarized calculations.
label of the atom as specified in ATOMIC_SPECIES
external force on atom X (cartesian components, Ha/a.u. units)
These are the indices of the states that you want to output.
Also used with calwf = 1 and 5. If calwf = 1, then you need
nwf indices here (each in a new line). If CALWF=5, then just
one index in needed.
Optional card, changes some variables on the fly of the calculation.
Notice that the rules has to be ordered in with time step and the
AUTOPILOT card has to be terminated with the ENDRULES keyword.
To set up a rule, one can add the scheduled steps with on_step and
separate the corresponding change in parameters with a column.
A simple example:AUTOPILOTon_step = 31 : dt = 5.0
on_step = 91 : iprint = 100
on_step = 91 : isave = 100
on_step = 191 : ion_dynamics = 'damp'
on_step = 191 : electron_damping = 0.00
on_step = 691 : ion_temperature = 'nose'
on_step = 691 : tempw = 150.0
ENDRULES