Molecular dynamics calculations: Difference between revisions

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== Combination of Ensembles and thermostats ==
== Combination of Ensembles and thermostats ==


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Revision as of 10:33, 29 May 2019

Compilation

First of all to run molecular dynamics calculation VASP has to be compiled using the -Dtbdyn precompiler flag in the makefile.include file. A sample input using this tag would look like this:

CPP     = $(CPP_) -DHOST=\"IFC9_fftw\" \
          -Dkind8 -DNGXhalf  -DCACHE_SIZE=12000 -DPGF90 -Davoidalloc  \
          -Dtbdyn

Main INCAR tags

  • IBRION=0: Molecular dynamics calculations are enabled by setting the IBRION tag to 0.
  • MDALGO: This tag selects the type of molecular dynamics calculations that is going to be executed (regular equations of motion, metadynamics etc.). It also includes the choice of ensemble, thermostat and barostat.


Combination of Ensembles and thermostats

Thermostat
Ensemble Andersen Nose-Hoover Langevin NHC CSVR Multiple Andersen
Microcanonical (NVE) MDALGO=1, ANDERSEN_PROB=0.0
Canonical (NVT) MDALGO=1 MDALGO=2 MDALGO=3 MDALGO=4 MDALGO=5 MDALGO=13
ISIF=2 ISIF=2 ISIF=2 ISIF=2 ISIF=2 ISIF=2
Isobaric-isothermal (NpT) not available not available MDALGO=3 not available not available not available
ISIF=3
Isoenthalpic-isobaric (NpH) MDALGO=3, ISIF=3, LANGEVIN_GAMMA=LANGEVIN_GAMMA_L=0.0

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Thermostat
Ensemble Andersen Nose-Hoover Langevin Multiple Andersen
NVE MDALGO=1 MDALGO=2 MDALGO=3 MDALGO=13
ISIF=0 ISIF=0 ISIF=0 ISIF=0
ANDERSEN_PROB=0.0 ANDERSEN_PROB=0.0
NVT MDALGO=1 MDALGO=2 MDALGO=3 MDALGO=13
ISIF=2 ISIF=2 ISIF=2 ISIF=2
NPT not available not available MDALGO=3 not available
ISIF=3