[Pw_forum] Problem determing the melting temperature of black phosphorene using molecular dynamics implemented in cp.x
barung at iitk.ac.in
barung at iitk.ac.in
Mon Feb 15 15:45:57 CET 2016
Dear QE,
We are trying to determine the stability of monolayer black phosphorous
using molecular dynamics with nose thermostat as implemented in cp.x.
However,even at very high temperature(around 5000K), the structure does
not melt though there are significant vibrations.
Kindly inform us whether the issue is associated with the nose frequency,
the initial random displacement, emass chosen or any other parameter.
We followed the procedures given in the cp.x user guide :
http://www.quantum-espresso.org/wp-content/uploads/Doc/cp_user_guide.pdf
We appreciate your replies with gratitude...
Barun Ghosh
PhD Student
Dept of Physics
IIT Kanpur
The input files are as follows:
STEP 1 ( Determining Electronic ground state - I)
&control
calculation='cp',
restart_mode='from_scratch',
nstep=200, iprint=20, isave=20,
dt=5,
ndr=90, ndw=91,
pseudo_dir='/home/barung/espresso/upf_files',
outdir='./output/',
/
&SYSTEM
ibrav = 0,
celldm(1) = 1.889725989,
nat = 36,
ntyp = 1,
ecutwfc = 120,
ecfixed = 14.0,
qcutz = 14.0,
q2sigma = 2.0
/
&electrons
electron_dynamics='damp',
electron_damping=0.1,
startingwfc='random', ampre=0.01,
orthogonalization='Gram-Schmidt',
emass=50, emass_cutoff=3.,
/
&ions
ion_radius(1)=1.0,
ion_dynamics='none'
/
ATOMIC_SPECIES
P 31.0 P.pbe-mt_fhi.UPF
ATOMIC_POSITIONS (angstrom)
P 0.4145944110 -1.6527352540 7.9416845570
P 0.4145944110 -4.9582057620 7.9416845570
P 0.4145944110 -8.2636762700 7.9416845570
P 11.1298393070 -3.3054705080 7.9501494580
P 11.1298393070 -6.6109410160 7.9501494580
P 11.1298393070 -9.9164115240 7.9501494580
P 11.9448235830 -3.3054705080 10.0578357590
P 11.9448235830 -6.6109410160 10.0578357590
P 11.9448235830 -9.9164115240 10.0578357590
P 13.4328383110 -1.6527352540 10.0541393780
P 13.4328383110 -4.9582057620 10.0541393780
P 13.4328383110 -8.2636762700 10.0541393780
P 1.9026219450 -3.3054705080 7.9467507480
P 1.9026219450 -6.6109410160 7.9467507480
P 1.9026219450 -9.9164115240 7.9467507480
P 2.7176062210 -3.3054705080 10.0544370490
P 2.7176062210 -6.6109410160 10.0544370490
P 2.7176062210 -9.9164115240 10.0544370490
P 4.2056209490 -1.6527352540 10.0507406680
P 4.2056209490 -4.9582057620 10.0507406680
P 4.2056209490 -8.2636762700 10.0507406680
P 5.0282030920 -1.6527352540 7.9433839120
P 5.0282030920 -4.9582057620 7.9433839120
P 5.0282030920 -8.2636762700 7.9433839120
P 6.5162306260 -3.3054705080 7.9484501030
P 6.5162306260 -6.6109410160 7.9484501030
P 6.5162306260 -9.9164115240 7.9484501030
P 7.3312149020 -3.3054705080 10.0561364040
P 7.3312149020 -6.6109410160 10.0561364040
P 7.3312149020 -9.9164115240 10.0561364040
P 8.8192296300 -1.6527352540 10.0524400230
P 8.8192296300 -4.9582057620 10.0524400230
P 8.8192296300 -8.2636762700 10.0524400230
P 9.6418117730 -1.6527352540 7.9450832670
P 9.6418117730 -4.9582057620 7.9450832670
P 9.6418117730 -8.2636762700 7.9450832670
CELL_PARAMETERS
0.0000000000 -9.9164115240 0.0000000000
13.8408260430 0.0000000000 0.0050980650
0.0073478690 0.0000000000 19.9945635070
STEP 2 ( Determining Electronic ground state - II )
&control
calculation='cp',
restart_mode='restart',
nstep=400, iprint=10, isave=50,
dt=5,
ndr=91, ndw=92,
pseudo_dir='/home/barung/espresso/upf_files',
outdir='./output/',
etot_conv_thr=1.e-6
/
&SYSTEM
ibrav = 0,
nat = 36,
celldm(1) = 1.889725989,
ntyp = 1,
ecutwfc = 120,
ecfixed = 14.0,
qcutz = 14.0,
q2sigma = 2.0
/
&electrons
electron_dynamics='damp',
electron_damping=2.0,
emass=100, emass_cutoff=3.,
/
&ions
ion_radius(1)=1.0,
ion_dynamics='none'
/
ATOMIC_SPECIES
P 31.0 P.pbe-mt_fhi.UPF
ATOMIC_POSITIONS (angstrom)
P 0.4145944110 -1.6527352540 7.9416845570
P 0.4145944110 -4.9582057620 7.9416845570
P 0.4145944110 -8.2636762700 7.9416845570
P 11.1298393070 -3.3054705080 7.9501494580
P 11.1298393070 -6.6109410160 7.9501494580
P 11.1298393070 -9.9164115240 7.9501494580
P 11.9448235830 -3.3054705080 10.0578357590
P 11.9448235830 -6.6109410160 10.0578357590
P 11.9448235830 -9.9164115240 10.0578357590
P 13.4328383110 -1.6527352540 10.0541393780
P 13.4328383110 -4.9582057620 10.0541393780
P 13.4328383110 -8.2636762700 10.0541393780
P 1.9026219450 -3.3054705080 7.9467507480
P 1.9026219450 -6.6109410160 7.9467507480
P 1.9026219450 -9.9164115240 7.9467507480
P 2.7176062210 -3.3054705080 10.0544370490
P 2.7176062210 -6.6109410160 10.0544370490
P 2.7176062210 -9.9164115240 10.0544370490
P 4.2056209490 -1.6527352540 10.0507406680
P 4.2056209490 -4.9582057620 10.0507406680
P 4.2056209490 -8.2636762700 10.0507406680
P 5.0282030920 -1.6527352540 7.9433839120
P 5.0282030920 -4.9582057620 7.9433839120
P 5.0282030920 -8.2636762700 7.9433839120
P 6.5162306260 -3.3054705080 7.9484501030
P 6.5162306260 -6.6109410160 7.9484501030
P 6.5162306260 -9.9164115240 7.9484501030
P 7.3312149020 -3.3054705080 10.0561364040
P 7.3312149020 -6.6109410160 10.0561364040
P 7.3312149020 -9.9164115240 10.0561364040
P 8.8192296300 -1.6527352540 10.0524400230
P 8.8192296300 -4.9582057620 10.0524400230
P 8.8192296300 -8.2636762700 10.0524400230
P 9.6418117730 -1.6527352540 7.9450832670
P 9.6418117730 -4.9582057620 7.9450832670
P 9.6418117730 -8.2636762700 7.9450832670
CELL_PARAMETERS
0.0000000000 -9.9164115240 0.0000000000
13.8408260430 0.0000000000 0.0050980650
0.0073478690 0.0000000000 19.9945635070
STEP 3 ( Random displacement of atoms from their equilibrium position )
&control
calculation='cp',
restart_mode='reset_counters',
nstep=4000, iprint=10, isave=100,
dt=3.0,
disk_io='high'
ndr=92, ndw=931,
pseudo_dir='/home/barung/espresso/upf_files',
outdir='./output/',
/
&SYSTEM
ibrav = 0,
celldm(1) = 1.889725989,
nat = 36,
ntyp = 1,
ecutwfc = 120,
ecfixed = 14.0,
qcutz = 14.0,
q2sigma = 2.0
/
&electrons
electron_dynamics='damp',
ortho_max=100,
emass=100, emass_cutoff=3.,
/
&ions
ion_dynamics='none',
ion_radius(1)=1.0
tranp(1)=.TRUE.
tranp(2)=.TRUE.
amprp(1)=0.01
amprp(2)=0.01
/
ATOMIC_SPECIES
P 31.0 P.pbe-mt_fhi.UPF
ATOMIC_POSITIONS (angstrom)
P 0.4145944110 -1.6527352540 7.9416845570
P 0.4145944110 -4.9582057620 7.9416845570
P 0.4145944110 -8.2636762700 7.9416845570
P 11.1298393070 -3.3054705080 7.9501494580
P 11.1298393070 -6.6109410160 7.9501494580
P 11.1298393070 -9.9164115240 7.9501494580
P 11.9448235830 -3.3054705080 10.0578357590
P 11.9448235830 -6.6109410160 10.0578357590
P 11.9448235830 -9.9164115240 10.0578357590
P 13.4328383110 -1.6527352540 10.0541393780
P 13.4328383110 -4.9582057620 10.0541393780
P 13.4328383110 -8.2636762700 10.0541393780
P 1.9026219450 -3.3054705080 7.9467507480
P 1.9026219450 -6.6109410160 7.9467507480
P 1.9026219450 -9.9164115240 7.9467507480
P 2.7176062210 -3.3054705080 10.0544370490
P 2.7176062210 -6.6109410160 10.0544370490
P 2.7176062210 -9.9164115240 10.0544370490
P 4.2056209490 -1.6527352540 10.0507406680
P 4.2056209490 -4.9582057620 10.0507406680
P 4.2056209490 -8.2636762700 10.0507406680
P 5.0282030920 -1.6527352540 7.9433839120
P 5.0282030920 -4.9582057620 7.9433839120
P 5.0282030920 -8.2636762700 7.9433839120
P 6.5162306260 -3.3054705080 7.9484501030
P 6.5162306260 -6.6109410160 7.9484501030
P 6.5162306260 -9.9164115240 7.9484501030
P 7.3312149020 -3.3054705080 10.0561364040
P 7.3312149020 -6.6109410160 10.0561364040
P 7.3312149020 -9.9164115240 10.0561364040
P 8.8192296300 -1.6527352540 10.0524400230
P 8.8192296300 -4.9582057620 10.0524400230
P 8.8192296300 -8.2636762700 10.0524400230
P 9.6418117730 -1.6527352540 7.9450832670
P 9.6418117730 -4.9582057620 7.9450832670
P 9.6418117730 -8.2636762700 7.9450832670
CELL_PARAMETERS
0.0000000000 -9.9164115240 0.0000000000
13.8408260430 0.0000000000 0.0050980650
0.0073478690 0.0000000000 19.9945635070
STEP 4 ( Molecular Dynamics using nose thermostat )
&control
calculation='cp',
restart_mode='reset_counters',
nstep=60000, iprint=10, isave=100,
dt=3.0,
ndr=92, ndw=932,
pseudo_dir='/home/barung/espresso/upf_files',
outdir='./output/',
disk_io='high'
/
&SYSTEM
ibrav = 0,
nat = 36,
ntyp = 1,
celldm(1) = 1.889725989,
ecutwfc = 120,
ecfixed = 14.0,
qcutz = 14.0,
q2sigma = 2.0
/
&electrons
electron_dynamics='damp',
ortho_max=100,
emass=100, emass_cutoff=3.,
/
&ions
ion_dynamics='verlet',
ion_temperature='nose',
tempw=4800, fnosep=20,
ion_radius(1)=1.0,
/
ATOMIC_SPECIES
P 31.0 P.pbe-mt_fhi.UPF
ATOMIC_POSITIONS (angstrom)
P 0.4145944110 -1.6527352540 7.9416845570
P 0.4145944110 -4.9582057620 7.9416845570
P 0.4145944110 -8.2636762700 7.9416845570
P 11.1298393070 -3.3054705080 7.9501494580
P 11.1298393070 -6.6109410160 7.9501494580
P 11.1298393070 -9.9164115240 7.9501494580
P 11.9448235830 -3.3054705080 10.0578357590
P 11.9448235830 -6.6109410160 10.0578357590
P 11.9448235830 -9.9164115240 10.0578357590
P 13.4328383110 -1.6527352540 10.0541393780
P 13.4328383110 -4.9582057620 10.0541393780
P 13.4328383110 -8.2636762700 10.0541393780
P 1.9026219450 -3.3054705080 7.9467507480
P 1.9026219450 -6.6109410160 7.9467507480
P 1.9026219450 -9.9164115240 7.9467507480
P 2.7176062210 -3.3054705080 10.0544370490
P 2.7176062210 -6.6109410160 10.0544370490
P 2.7176062210 -9.9164115240 10.0544370490
P 4.2056209490 -1.6527352540 10.0507406680
P 4.2056209490 -4.9582057620 10.0507406680
P 4.2056209490 -8.2636762700 10.0507406680
P 5.0282030920 -1.6527352540 7.9433839120
P 5.0282030920 -4.9582057620 7.9433839120
P 5.0282030920 -8.2636762700 7.9433839120
P 6.5162306260 -3.3054705080 7.9484501030
P 6.5162306260 -6.6109410160 7.9484501030
P 6.5162306260 -9.9164115240 7.9484501030
P 7.3312149020 -3.3054705080 10.0561364040
P 7.3312149020 -6.6109410160 10.0561364040
P 7.3312149020 -9.9164115240 10.0561364040
P 8.8192296300 -1.6527352540 10.0524400230
P 8.8192296300 -4.9582057620 10.0524400230
P 8.8192296300 -8.2636762700 10.0524400230
P 9.6418117730 -1.6527352540 7.9450832670
P 9.6418117730 -4.9582057620 7.9450832670
P 9.6418117730 -8.2636762700 7.9450832670
CELL_PARAMETERS
0.0000000000 -9.9164115240 0.0000000000
13.8408260430 0.0000000000 0.0050980650
0.0073478690 0.0000000000 19.9945635070
More information about the users
mailing list