TABLE OF CONTENTS
INTRODUCTION
&CONTROL
calculation  title  verbosity  isave  restart_mode  nstep  iprint  tstress  tprnfor  dt  outdir  saverho  prefix  ndr  ndw  tabps  max_seconds  etot_conv_thr  forc_conv_thr  ekin_conv_thr  disk_io  memory  pseudo_dir  tefield
&SYSTEM
ibrav  celldm  A  B  C  cosAB  cosAC  cosBC  nat  ntyp  nbnd  tot_charge  tot_magnetization  ecutwfc  ecutrho  nr1  nr2  nr3  nr1s  nr2s  nr3s  nr1b  nr2b  nr3b  occupations  degauss  smearing  nspin  ecfixed  qcutz  q2sigma  input_dft  exx_fraction  lda_plus_u  Hubbard_U  vdw_corr  london_s6  london_rcut  ts_vdw  ts_vdw_econv_thr  ts_vdw_isolated  assume_isolated
&ELECTRONS
electron_maxstep  electron_dynamics  conv_thr  niter_cg_restart  efield  epol  emass  emass_cutoff  orthogonalization  ortho_eps  ortho_max  ortho_para  electron_damping  electron_velocities  electron_temperature  ekincw  fnosee  startingwfc  tcg  maxiter  passop  n_inner  ninter_cold_restart  lambda_cold  grease  ampre
&IONS
ion_dynamics  ion_positions  ion_velocities  ion_damping  ion_radius  iesr  ion_nstepe  remove_rigid_rot  ion_temperature  tempw  fnosep  tolp  nhpcl  nhptyp  nhgrp  fnhscl  ndega  tranp  amprp  greasp
&CELL
cell_parameters  cell_dynamics  cell_velocities  cell_damping  press  wmass  cell_factor  cell_temperature  temph  fnoseh  greash  cell_dofree
&PRESS_AI
abivol  abivol  P_ext  pvar  P_in  P_fin  Surf_t  rho_thr  dthr
&WANNIER
wf_efield  wf_switch  sw_len  efx0  efy0  efz0  efx1  efy1  efz1  wfsd  wfdt  maxwfdt  nit  nsd  wf_q  wf_friction  nsteps  tolw  adapt  calwf  nwf  wffort  writev  exx_neigh  exx_dis_cutoff  exx_poisson_eps  exx_ps_rcut_self  exx_ps_rcut_pair  exx_me_rcut_self  exx_me_rcut_pair
ATOMIC_SPECIES
X  Mass_X  PseudoPot_X
ATOMIC_POSITIONS
X  x  y  z  if_pos(1)  if_pos(2)  if_pos(3)
ATOMIC_VELOCITIES
V  vx  vy  vz
CELL_PARAMETERS
v1  v2  v3
REF_CELL_PARAMETERS
v1  v2  v3
CONSTRAINTS
nconstr  constr_tol  constr_type  constr(1)  constr(2)  constr(3)  constr(4)  constr_target
OCCUPATIONS
f_inp1  f_inp2
ATOMIC_FORCES
X  fx  fy  fz
PLOT_WANNIER
iwf
AUTOPILOT
pilot_rule
INTRODUCTION
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, DOS <CR><LF> CHARACTERS ARE POTENTIAL SOURCES OF TROUBLE
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.
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) ]
Namelist: &CONTROL

calculation 
CHARACTER 
Default: 
'cp'

a string describing the task to be performed:
'cp',
'scf',
'nscf',
'relax',
'vcrelax',
'vccp',
'cpwf',
'vccpwf'
(vc = variablecell).
(wf = Wannier functions).

title 
CHARACTER 
Default: 
'MD Simulation '

reprinted on output.

verbosity 
CHARACTER 
Default: 
'low'

In order of decreasing verbose output:
'debug'  'high'  'medium'  'low','default'  'minimal'

isave 
INTEGER 
Default: 
100

See: 
ndr 
See: 
ndw 
Number of steps between successive savings of
information needed to restart the run.

restart_mode 
CHARACTER 
Default: 
'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

nstep 
INTEGER 
Default: 
50

number of CarParrinello steps performed in this run

iprint 
INTEGER 
Default: 
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.

tstress 
LOGICAL 
Default: 
.false.

Write stress tensor to standard output each "iprint" steps.
It is set to .TRUE. automatically if
calculation='vcrelax'

tprnfor 
LOGICAL 
Default: 
.false.

print forces. Set to .TRUE. when ions are moving.

dt 
REAL 
Default: 
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!!!)

outdir 
CHARACTER 
Default: 
value of the ESPRESSO_TMPDIR environment variable if set;
current directory ('./') otherwise

input, temporary, trajectories and output files are found
in this directory.

saverho 
LOGICAL 
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.

prefix 
CHARACTER 
Default: 
'cp'

prepended to input/output filenames:
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 (tsvdw)
prefix.eig : eigen values
prefix.nos : NoseHoover variables
prefix.spr : spread of Wannier orbitals
prefix.wfc : center of Wannier orbitals
prefix.ncg : number of Poisson CG steps (PBE0)

ndr 
INTEGER 
Default: 
50

Units for input and output restart file.

ndw 
INTEGER 
Default: 
50

Units for input and output restart file.

tabps 
LOGICAL 
Default: 
.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)).

max_seconds 
REAL 
Default: 
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.

etot_conv_thr 
REAL 
Default: 
1.0D4

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

forc_conv_thr 
REAL 
Default: 
1.0D3

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

ekin_conv_thr 
REAL 
Default: 
1.0D6

convergence criterion for electron minimization:
convergence is achieved when "ekin < ekin_conv_thr".
See also etot_conv_thr  both criteria must be satisfied.

disk_io 
CHARACTER 
Default: 
'default'

'high': CP code will write KohnSham wfc files and additional
information in datafile.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.

memory 
CHARACTER 
Default: 
'default'

'small': memorysaving tricks are implemented. Currently:
 the Gvectors 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 reread the data file

pseudo_dir 
CHARACTER 
Default: 
value of the $ESPRESSO_PSEUDO environment variable if set;
'$HOME/espresso/pseudo/' otherwise

directory containing pseudopotential files

tefield 
LOGICAL 
Default: 
.FALSE.

If .TRUE. a homogeneous finite electric field described
through the modern theory of the polarization is applied.



Namelist: &SYSTEM

ibrav 
INTEGER 
Status: 
REQUIRED

Bravaislattice 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,cosab,cosac,cosbc
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)
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(alpha)
The crystallographic vectors form a threefold star around
the zaxis, 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(alpha) is the cosine of the angle alpha between
any pair of crystallographic vectors, tx, ty, tz are:
tx=sqrt((1c)/2), ty=sqrt((1c)/6), tz=sqrt((1+2c)/3)
5 Trigonal R, 3fold axis <111> celldm(4)=cos(alpha)
The crystallographic vectors form a threefold 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 basecentered(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 facecentered 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 bodycentered 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 basecentered celldm(2)=b/a
celldm(3)=c/a,
celldm(4)=cos(ab)
v1 = ( a/2, 0, c/2),
v2 = (b*cos(gamma), b*sin(gamma), 0),
v3 = ( a/2, 0, c/2),
where gamma is the angle between axis a and b
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)^2cos(beta)^2cos(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

Either:
celldm(i), i=1,6 
REAL 
See: 
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

Or:
A, B, C, cosAB, cosAC, cosBC 
REAL 
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


nat 
INTEGER 
Status: 
REQUIRED

number of atoms in the unit cell

ntyp 
INTEGER 
Status: 
REQUIRED

number of types of atoms in the unit cell

nbnd 
INTEGER 
Default: 
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 spinpolarized calculations the number of
kpoint, not the number of bands per kpoint, is doubled

tot_charge 
REAL 
Default: 
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.

tot_magnetization 
REAL 
Default: 
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.

ecutwfc 
REAL 
Status: 
REQUIRED

kinetic energy cutoff (Ry) for wavefunctions

ecutrho 
REAL 
Default: 
4 * ecutwfc

kinetic energy cutoff (Ry) for charge density and potential
For normconserving 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 gradientcorrected functional, especially in cells
with vacuum, or for pseudopotential without nonlinear core
correction, usually requires an higher values of ecutrho
to be accurately converged.

nr1, nr2, nr3 
INTEGER 
See: 
ecutrho 
threedimensional FFT mesh (hard grid) for charge
density (and scf potential). If not specified
the grid is calculated based on the cutoff for
charge density.

nr1s, nr2s, nr3s 
INTEGER 
threedimensional mesh for wavefunction FFT and for the smooth
part of charge density ( smooth grid ).
Coincides with nr1, nr2, nr3 if ecutrho = 4 * ecutwfc ( default )

nr1b, nr2b, nr3b 
INTEGER 
dimensions of the "box" grid for Ultrasoft pseudopotentials
must be specified if Ultrasoft PP are present

occupations 
CHARACTER 
a string describing the occupation of the electronic states.
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

degauss 
REAL 
Default: 
0.D0 Ry

parameter for the smearing function, only used for ensemble DFT
calculations

smearing 
CHARACTER 
a string describing the kind of occupations for electronic states
in the case of ensemble DFT (occupations == 'ensemble' );
now only FermiDirac ('fd') case is implemented

nspin 
INTEGER 
Default: 
1

nspin = 1 : nonpolarized calculation (default)
nspin = 2 : spinpolarized calculation, LSDA
(magnetization along z axis)

ecfixed 
REAL 
Default: 
0.0

See: 
q2sigma 
qcutz 
REAL 
Default: 
0.0

See: 
q2sigma 
q2sigma 
REAL 
Default: 
0.1

ecfixed, qcutz, q2sigma: parameters for modified functional to be
used in variablecell molecular dynamics (or in stress calculation).
"ecfixed" is the value (in Rydberg) of the constantcutoff;
"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)

input_dft 
CHARACTER 
Default: 
read from pseudopotential files

Exchangecorrelation 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: 'cpwf' and 'vccpwf'
See CP specific user manual for further guidance (or in CPV/Doc/user_guide.tex)
and examples in CPV/examples/EXXwfexample.
Also see related keywords starting with exx_.

exx_fraction 
REAL 
Default: 
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.

lda_plus_u 
LOGICAL 
Default: 
.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).

Hubbard_U(i), i=1,ntyp 
REAL 
Default: 
0.D0 for all species

Status: 
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, oneparameter LDA+U is
implemented (no "alpha" or "J" terms)

vdw_corr 
CHARACTER 
Default: 
'none'

Type of Van der Waals correction. Allowed values:
'grimmed2', 'GrimmeD2', 'DFTD', 'dftd': semiempirical Grimme's DFTD2.
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', 'tsvdw', 'tsvdW', 'tkatchenkoscheffler': TkatchenkoScheffler
dispersion corrections with firstprinciple derived C6 coefficients
Optional variables: "ts_vdw_econv_thr", "ts_vdw_isolated"
See A. Tkatchenko and M. Scheffler, Phys. Rev. Lett. 102, 073005 (2009)
'XDM', 'xdm': Exchangehole dipolemoment 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 nonlocal functionals (eg vdwDF) are NOT specified here but in "input_dft"

london_s6 
REAL 
Default: 
0.75

global scaling parameter for DFTD. Default is good for PBE.

london_rcut 
REAL 
Default: 
200

cutoff radius (a.u.) for dispersion interactions

ts_vdw 
LOGICAL 
Default: 
.FALSE.

OBSOLESCENT, same as vdw_corr='TS'

ts_vdw_econv_thr 
REAL 
Default: 
1.D6

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

ts_vdw_isolated 
LOGICAL 
Default: 
.FALSE.

Optional: set it to .TRUE. when computing the TkatchenkoScheffler vdW energy
for an isolated (nonperiodic) system.

assume_isolated 
CHARACTER 
Default: 
'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.
'makovpayne', 'mp', 'mp' : the MakovPayne 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)



Namelist: &ELECTRONS

electron_maxstep 
INTEGER 
Default: 
100

maximum number of iterations in a scf step

electron_dynamics 
CHARACTER 
Default: 
'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 BornOppenheimer 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.

conv_thr 
REAL 
Default: 
1.D6

Convergence threshold for selfconsistency:
estimated energy error < conv_thr

niter_cg_restart 
INTEGER 
Default: 
20

frequency in iterations for which the conjugategradient algorithm
for electronic relaxation is restarted

efield 
REAL 
Default: 
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.

epol 
INTEGER 
Default: 
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

emass 
REAL 
Default: 
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 )

emass_cutoff 
REAL 
Default: 
2.5D0

mass cutoff (in Rydberg) for the Fourier acceleration
effective mass is rescaled for "G" vector components with
kinetic energy above "emass_cutoff"

orthogonalization 
CHARACTER 
Default: 
'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 GramSchmidt instead just
to start the simulation
'GramSchmidt' : use GramSchmidt algorithm  to be used ONLY in
the first few steps.
YIELDS INCORRECT ENERGIES AND EIGENVALUES.

ortho_eps 
REAL 
Default: 
1.D8

tolerance for iterative orthonormalization
meaningful only if orthogonalization = 'ortho'

ortho_max 
INTEGER 
Default: 
20

maximum number of iterations for orthonormalization
meaningful only if orthogonalization = 'ortho'

ortho_para 
INTEGER 
Default: 
0

Status: 
OBSOLETE: use commandline option " nd XX" instead


electron_damping 
REAL 
Default: 
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' "

electron_velocities 
CHARACTER 
'zero' : restart setting electronic velocities to zero
'default' : restart using electronic velocities of the
previous run

electron_temperature 
CHARACTER 
Default: 
'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.

ekincw 
REAL 
Default: 
0.001D0

value of the average kinetic energy (in atomic units) forced
by the temperature control
meaningful only with " electron_temperature /= 'not_controlled' "

fnosee 
REAL 
Default: 
1.D0

oscillation frequency of the nose thermostat (in terahertz)
meaningful only with " electron_temperature = 'nose' "

startingwfc 
CHARACTER 
Default: 
'random'

'atomic': start from superposition of atomic orbitals
(not yet implemented)
'random': start from random wfcs. See "ampre".

tcg 
LOGICAL 
Default: 
.FALSE.

if .TRUE. perform a conjugate gradient minimization of the
electronic states for every ionic step.
It requires GramSchmidt orthogonalization of the electronic
states.

maxiter 
INTEGER 
Default: 
100

maximum number of conjugate gradient iterations for
conjugate gradient minimizations of electronic states

passop 
REAL 
Default: 
0.3D0

small step used in the conjugate gradient minimization
of the electronic states.

n_inner 
INTEGER 
Default: 
2

number of internal cycles for every conjugate gradient
iteration only for ensemble DFT

ninter_cold_restart 
INTEGER 
Default: 
1

frequency in iterations at which a full inner cycle, only
for cold smearing, is performed

lambda_cold 
REAL 
Default: 
0.03D0

step for inner cycle with cold smearing, used when a not full
cycle is performed

grease 
REAL 
Default: 
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

ampre 
REAL 
Default: 
0.D0

amplitude of the randomization ( allowed values: 0.0  1.0 )
meaningful only if " startingwfc = 'random' "



Namelist: &IONS

input this namelist only if calculation = 'cp', 'relax', 'vcrelax', 'vccp', 'cpwf', 'vccpwf'
ion_dynamics 
CHARACTER 
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

ion_positions 
CHARACTER 
Default: 
'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.

ion_velocities 
CHARACTER 
Default: 
'default'

See: 
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
'random' : start the simulation with random atomic velocities
'from_input' : restart the simulation with atomic velocities read
from standard input  see card 'ATOMIC_VELOCITIES'
BEWARE: works only if restart_mode='from_scratch',
tested only with electrons_dynamics='cg'
'zero' : restart the simulation with atomic velocities set
to zero

ion_damping 
REAL 
Default: 
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' "

ion_radius(i), i=1,ntyp 
REAL 
Default: 
0.5 a.u. for all species

ion_radius(i): pseudoatomic radius of the ith 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".

iesr 
INTEGER 
Default: 
1

The realspace contribution to the Ewald summation is performed
on iesr*iesr*iesr cells. Typically iesr=1 is sufficient to have
converged results.

ion_nstepe 
INTEGER 
Default: 
1

number of electronic steps per ionic step.

remove_rigid_rot 
LOGICAL 
Default: 
.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.

ion_temperature 
CHARACTER 
Default: 
'not_controlled'

'nose' : control ionic temperature using NoseHoover
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

tempw 
REAL 
Default: 
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

fnosep 
REAL 
Default: 
1.D0

oscillation frequency of the nose thermostat (in terahertz)
[note that 3 terahertz = 100 cm^1]
meaningful only with " ion_temperature = 'nose' "
for NoseHoover 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.

tolp 
REAL 
Default: 
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' "
and with ion_velocities='change_step', where it specifies
the old timestep

nhpcl 
INTEGER 
Default: 
1

number of thermostats in the NoseHoover chain
currently maximum allowed is 4

nhptyp 
INTEGER 
Default: 
0

type of the "massive" NoseHoover 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

nhgrp(i), i=1,ntyp 
INTEGER 
Default: 
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 nonupdated thermostat
for Li which will effectively make temperature for Li "not controlled"

fnhscl(i), i=1,ntyp 
REAL 
Default: 
(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, CH 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

ndega 
INTEGER 
Default: 
0

number of degrees of freedom used for temperature calculation
ndega <= 0 sets the number of degrees of freedom to
[3*natabs(ndega)], ndega > 0 is used as the target number

tranp(i), i=1,ntyp 
LOGICAL 
Default: 
.false.

See: 
amprp 
If .TRUE. randomize ionic positions for the
atomic type corresponding to the index.

amprp(i), i=1,ntyp 
REAL 
Default: 
0.D0

See: 
amprp 
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.".

greasp 
REAL 
Default: 
1.D0

same as "grease", for ionic damped dynamics.



Namelist: &CELL

input this namelist only if calculation = 'vcrelax', 'vccp', 'vccpwf'
cell_parameters 
CHARACTER 
'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' )

cell_dynamics 
CHARACTER 
Default: 
'none'

set how cell should be moved
'none' : cell is kept fixed
'sd' : steepest descent algorithm is used to optimise the
cell
'damppr' : damped dynamics is used to optimise the cell
( ParrinelloRahman method ).
'pr' : standard Verlet algorithm is used to propagate
the cell ( ParrinelloRahman method ).

cell_velocities 
CHARACTER 
'zero' : restart setting cell velocity to zero
'default' : restart using cell velocity of the previous run

cell_damping 
REAL 
Default: 
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' "

press 
REAL 
Default: 
0.D0

Target pressure [KBar] in a variablecell md or relaxation run.

wmass 
REAL 
Default: 
0.75*Tot_Mass/pi**2 for ParrinelloRahman MD;
0.75*Tot_Mass/pi**2/Omega**(2/3) for Wentzcovitch MD

Fictitious cell mass [amu] for variablecell simulations
(both 'vcmd' and 'vcrelax')

cell_factor 
REAL 
Default: 
1.2D0

Used in the construction of the pseudopotential tables.
It should exceed the maximum linear contraction of the
cell during a simulation.

cell_temperature 
CHARACTER 
Default: 
'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.

temph 
REAL 
Default: 
0.D0

value of the cell temperature (in ???) forced
by the temperature control.
meaningful only with " cell_temperature /= 'not_controlled' "

fnoseh 
REAL 
Default: 
1.D0

oscillation frequency of the nose thermostat (in terahertz)
meaningful only with " cell_temperature = 'nose' "

greash 
REAL 
Default: 
1.D0

same as "grease", for cell damped dynamics

cell_dofree 
CHARACTER 
Default: 
'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.



Namelist: &PRESS_AI

input this namelist only when tabps = .true.
abivol 
LOGICAL 
Default: 
.false.

.true. for finite pressure calculations

abivol 
LOGICAL 
Default: 
.false.

.true. for finite surface tension calculations

P_ext 
REAL 
Default: 
0.D0

external pressure in GPa

pvar 
LOGICAL 
Default: 
.false.

.true. for variable pressure calculations
pressure changes linearly with time:
Delta_P = (P_fin  P_in)/nstep

P_in 
REAL 
Default: 
0.D0

only if pvar = .true.
initial value of the external pressure (GPa)

P_fin 
REAL 
Default: 
0.D0

only if pvar = .true.
final value of the external pressure (GPa)

Surf_t 
REAL 
Default: 
0.D0

Surface tension (in a.u.; typical values 1.d4  1.d3)

rho_thr 
REAL 
Default: 
0.D0

threshold parameter which defines the electronic charge density
isosurface to compute the 'quantum' volume of the system
(typical values: 1.d4  1.d3)
(corresponds to alpha in PRL 94 145501 (2005))

dthr 
REAL 
Default: 
0.D0

thikness of the external skin of the electronic charge density
used to compute the 'quantum' surface
(typical values: 1.d4  1.d3; 50% to 100% of rho_thr)
(corresponds to Delta in PRL 94 145501 (2005))



Namelist: &WANNIER

only if calculation = 'cpwf', 'vccpwf'
Output files used by Wannier Function options are the following
fort.21: Used only when calwf=5, contains the full list of gvecs.
fort.22: Used Only when calwf=5, contains the coeffs. corresponding
to the gvectors 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 gvectors (basis vectors) are
written to unit 21. This option gives the gvecs 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.
wf_efield 
LOGICAL 
Default: 
.false.

If dynamics will be done in the presence of a field

wf_switch 
LOGICAL 
Default: 
.false.

Whether to turn on the field adiabatically (adiabatic switch)
if true, then nbeg is set to 0.

sw_len 
INTEGER 
Default: 
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.

efx0, efy0, efz0 
REAL 
See: 
0.D0 
Initial values of the field along x, y, and z directions

efx1, efy1, efz1 
REAL 
See: 
0.D0 
Final values of the field along x, y, and z directions

wfsd 
INTEGER 
Default: 
1

Localization algorithm for Wannier function calculation:
wfsd=1 Damped Dynamics
wfsd=2 SteepestDescent / ConjugateGradient
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.

wfdt 
REAL 
Default: 
5.D0

The minimum step size to take in the SD/CG direction

maxwfdt 
REAL 
Default: 
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)

nit 
INTEGER 
Default: 
10

Number of iterations to do for Wannier convergence.

nsd 
INTEGER 
Default: 
10

Out of a total of NIT iterations, NSD will be SteepestDescent
and ( nit  nsd ) will be ConjugateGradient.

wf_q 
REAL 
Default: 
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 antihermitian matrix. The DampedDynamics 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.

wf_friction 
REAL 
Default: 
0.3D0

Damping coefficient for DampedDynamics.

nsteps 
INTEGER 
Default: 
20

Number of DampedDynamics steps to be performed per CP
iteration.

tolw 
REAL 
Default: 
1.D8

Convergence criterion for localization.

adapt 
LOGICAL 
Default: 
.true.

Whether to adapt the damping parameter dynamically.

calwf 
INTEGER 
Default: 
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_iexp{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 KohnSham 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 DampedDynamics 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.

nwf 
INTEGER 
Default: 
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.

wffort 
INTEGER 
Default: 
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.

writev 
LOGICAL 
Default: 
.false.

Output the charge density (gspace) and the list of gvectors
This is useful if you want to reconstruct the electrostatic
potential using the Poisson equation. If .TRUE. then the
code will output the gspace charge density and the list
if Gvectors, 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
Gvectors are written to G_PARA or G_SERL.

exx_neigh 
INTEGER 
Default: 
60

An initial guess on the maximum number of neighboring (overlapping) Wannier functions.

exx_dis_cutoff 
REAL 
Default: 
8.0

Radial cutoff distance (in bohr) for including overlapping Wannier function pairs
in EXX calculations.

exx_poisson_eps 
REAL 
Default: 
1.0D6

Poisson solver convergence criterion during computation of the EXX potential.

exx_ps_rcut_self 
REAL 
Default: 
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 Wannier function center, and should be large enough to cover
the majority of the orbital charge density.

exx_ps_rcut_pair 
REAL 
Default: 
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 Wannier functions, and should be
large enough to cover the majority of the orbital overlap charge density.
This parameter can generally be chosen as smaller than exx_ps_rcut_self.

exx_me_rcut_self 
REAL 
Default: 
10.0

Radial cutoff distance (in bohr) for the multipoleexpansion sphere
centered at a given Wannier function center.
The farfield self EXX potential in this sphere is generated with
multipole expansion of the orbital charge density.

exx_me_rcut_pair 
REAL 
Default: 
7.0

Radial cutoff distance (in bohr) for the multipoleexpansion sphere
centered at the midpoint of two overlapping Wannier functions.
The farfield pair EXX potential in this sphere is generated with
a multipole expansion of the orbital overlap charge density.
This parameter can generally be chosen as smaller than exx_me_rcut_self.



Card: ATOMIC_SPECIES 
Syntax:
ATOMIC_SPECIES

Description of items:
X 
CHARACTER 
label of the atom. Acceptable syntax:
chemical symbol X (1 or 2 characters, caseinsensitive)
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_X 
REAL 
mass of the atomic species [amu: mass of C = 12]
not used if calculation='scf', 'nscf', 'bands'

PseudoPot_X 
CHARACTER 
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 normconserving format



Card: ATOMIC_POSITIONS { alat  bohr  angstrom  crystal } 
IF calculation == 'bands' OR calculation == 'nscf' :
Specified atomic positions will be IGNORED and those from the
previous scf calculation will be used instead !!!

ELSEIF :
Syntax:
ATOMIC_POSITIONS { alat  bohr  angstrom  crystal
}



Description of items:
Card's options: 
alat  bohr  angstrom  crystal

Default: 
(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

X 
CHARACTER 
label of the atom as specified in ATOMIC_SPECIES

x, y, z

REAL 
atomic positions

if_pos(1), if_pos(2), if_pos(3)

INTEGER 
Default: 
1

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.



Card: ATOMIC_VELOCITIES { a.u } 
Optional card, reads velocities (in atomic units) from standard input
when starting with ion_velocities="from_input" it is convenient
to perform few steps (~510) with a smaller time step (0.5 a.u.)
Syntax:
ATOMIC_VELOCITIES { a.u
}

Description of items:
V 
CHARACTER 
label of the atom as specified in ATOMIC_SPECIES

vx, vy, vz

REAL 
atomic velocities along x y and z direction



Card: CELL_PARAMETERS { bohr  angstrom  alat } 
Optional card, needed only if ibrav = 0 is specified, ignored otherwise !
Syntax:
CELL_PARAMETERS { bohr  angstrom  alat
}

Description of items:
Card's options: 
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

v1, v2, v3

REAL 
Crystal lattice vectors:
v1(1) v1(2) v1(3) ... 1st lattice vector
v2(1) v2(2) v2(3) ... 2nd lattice vector
v3(1) v3(2) v3(3) ... 3rd lattice vector



Card: REF_CELL_PARAMETERS { bohr  angstrom } 
Optional card, needed only if one wants to do variable cell calculations accurately.
The reference cell generates additional buffer planewaves.
Syntax:
REF_CELL_PARAMETERS { bohr  angstrom
}

Description of items:
Card's options: 
bohr  angstrom

bohr / angstrom: reference cell parameters in bohr radii / angstrom.
To mimic a constant effective planewave kinetic energy (ecfixed) during a
variablecell 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 variablecell 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.

v1, v2, v3

REAL 
REF_CELL_PARAMETERS { bohr  angstrom }
v1(1) v1(2) v1(3) ... 1st reference lattice vector
v2(1) v2(2) v2(3) ... 2nd reference lattice vector
v3(1) v3(2) v3(3) ... 3rd reference lattice vector



Card: CONSTRAINTS 
Optional card, used for constrained dynamics or constrained optimisations
When this card is present the SHAKE algorithm is automatically used.
Syntax:
CONSTRAINTS

Description of items:
nconstr 
INTEGER 
Number of constraints.

constr_tol 
REAL 
Tolerance for keeping the constraints satisfied.

constr_type 
CHARACTER 
Type of constrain :
'type_coord' : constraint on global coordinationnumber, i.e. the
average number of atoms of type B surrounding the
atoms of type A. The coordination is defined by
using a FermiDirac.
(four indexes must be specified).
'atom_coord' : constraint on local coordinationnumber, i.e. the
average number of atoms of type A surrounding a
specific atom. The coordination is defined by
using a FermiDirac.
(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 ).

constr(1), constr(2), constr(3), constr(4)


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 cutoff 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 cutoff 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.

constr_target 
REAL 
Target for the constrain ( angles are specified in degrees ).
This variable is optional.



Card: OCCUPATIONS 
Optional card, used only if occupations = 'from_input', ignored otherwise !
Syntax:
OCCUPATIONS

Description of items:
f_inp1 
REAL 
Occupations of individual states (MAX 10 PER LINE).
For spinpolarized calculations, these are majority spin states.

f_inp2 
REAL 
Occupations of minority spin states (MAX 10 PER LINE)
To be specified only for spinpolarized calculations.



Card: ATOMIC_FORCES 
Optional card used to specify external forces acting on atoms
Syntax:
ATOMIC_FORCES

Description of items:
X 
CHARACTER 
label of the atom as specified in ATOMIC_SPECIES

fx, fy, fz

REAL 
external force on atom X (cartesian components, Ha/a.u. units)



Card: PLOT_WANNIER 
Optional card, indices of the states that have to be printed (only for calf=1 and calf=5).
Syntax:
PLOT_WANNIER

Description of items:
iwf 
INTEGER 
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.



Card: AUTOPILOT 
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 Card has
to be terminated with "ENDRULES"
Syntax:
AUTOPILOT

Description of items:
pilot_rule 
RULE 
To set up a rule, one can add the scheduled steps with on_step and
separate the corresponding change in parameters with a column.
See a simple example bellow:
AUTOPILOT
on_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



