H2O molecular dynamics: Difference between revisions

From VASP Wiki
No edit summary
No edit summary
Line 1: Line 1:
*{{TAG|INCAR}}
{{Template:At_and_mol}}
 
== Task ==
 
== Input ==
 
=== {{TAG|POSCAR}} ===
H2O _2
0.52918  ! scaling parameter
  12 0 0
  0 12 0
  0 0 12
1 2
select
cart
      0.00    0.00    0.00 T T F
      1.10    -1.43    0.00 T T F
      1.10    1.43    0.00 T T F
 
=== {{TAG|INCAR}} ===
  {{TAGBL|PREC}} = Normal    ! standard precision  
  {{TAGBL|PREC}} = Normal    ! standard precision  
  {{TAGBL|ENMAX}} = 400      ! cutoff should be set manually
  {{TAGBL|ENMAX}} = 400      ! cutoff should be set manually
Line 10: Line 29:
  {{TAGBL|TEBEG}} =  2000 ; {{TAGBL|TEEND}} = 2000 ! temperature
  {{TAGBL|TEBEG}} =  2000 ; {{TAGBL|TEEND}} = 2000 ! temperature


*{{TAG|KPOINTS}}
=== {{TAG|KPOINTS}} ===
  Gamma-point only
  Gamma-point only
   0
   0
Line 17: Line 36:
   0 0 0
   0 0 0


*{{TAG|POSCAR}}
== Calculation ==
H2O _2
0.52918  ! scaling parameter
  12 0 0
  0 12 0
  0 0 12
1 2
select
cart
      0.00    0.00    0.00 T T F
      1.10    -1.43    0.00 T T F
      1.10    1.43    0.00 T T F


the pair correlation function can be visualized using e.g. the following script:
The pair correlation function can be visualized using e.g. the following script:


*plot_PCDAT
*plot_PCDAT

Revision as of 08:58, 27 April 2017

Task

Input

POSCAR

H2O _2
0.52918   ! scaling parameter
 12 0 0
 0 12 0
 0 0 12
1 2
select
cart
     0.00     0.00     0.00 T T F
     1.10    -1.43     0.00 T T F
     1.10     1.43     0.00 T T F

INCAR

PREC = Normal    ! standard precision 
ENMAX = 400      ! cutoff should be set manually
ISMEAR = 0 ; SIGMA = 0.1
ISYM = 0         ! strongly recommended for MD
IBRION = 0       ! molecular dynamics
NSW = 100        ! 100 steps
POTIM = 1.0      ! timestep 1 fs
SMASS = -3       ! Nose Hoover thermostat
TEBEG =  2000 ; TEEND = 2000 ! temperature

KPOINTS

Gamma-point only
 0
Monkhorst Pack
 1 1 1
 0 0 0

Calculation

The pair correlation function can be visualized using e.g. the following script:

  • plot_PCDAT
awk <PCDAT >PCDAT.dat '
NR==8 { pcskal=$1}
NR==9 { pcfein=$1}
NR>=13 {
 line=line+1
 if (line==257)  {
    print " "
    line=0
 }
 else
    print (line-0.5)*pcfein/pcskal,$1
}
'
cat >plotfile<<!
# set term postscript enhanced colour lw 2 "Helvetica" 20
# set output "pair_correlation.eps"
set title "pair-correlation of H2O at 2000 K"
set xlabel "r [Angstrom]"
set ylabel "g(r)"
plot [0:15] "PCDAT.dat"  w lines
!
gnuplot -persist plotfile

Download

H2Omd.tgz


To the list of examples or to the main page