Molecular dynamics calculations: Difference between revisions
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== Main INCAR tags == | == Main INCAR tags == | ||
*{{TAG|IBRION}}=0: Molecular dynamics calculations are enabled by setting the {{TAG|IBRION}} tag to 0. | *{{TAG|IBRION}}=0: Molecular dynamics calculations are enabled by setting the {{TAG|IBRION}} tag to 0. | ||
*{{TAG|MDALGO}}: This tag selects the type of thermostat used in the molecular dynamics calculations. For regular molecular dynamics calculations the thermostat is selected by a one digit number (e.g. 1 for Andersen, 2 for Nose-Hoover etc.). For biased molecular dynamics, metadynamics etc. the thermostat is selected by a two digit number where the first digit corresponds to the thermostat analogously to regular molecular dynamics and the second digit corresponds to the molecular dynamics type (e.g. 11 metadynamics with Andersen thermostat, 21 metadynamics with Nose-Hoover thermostat etc.). | *{{TAG|MDALGO}}: This tag selects the type of thermostat used in the molecular dynamics calculations. For regular molecular dynamics calculations the thermostat is selected by a one digit number (e.g. 1 for Andersen, 2 for Nose-Hoover etc.). For biased molecular dynamics, metadynamics etc. the thermostat is selected by a two digit number where the first digit corresponds to the thermostat analogously to regular molecular dynamics and the second digit corresponds to the molecular dynamics type (e.g. 11 metadynamics with Andersen thermostat, 21 metadynamics with Nose-Hoover thermostat etc.). The NVE ensemble is a special case. It is available by selecting the Andersen thermostat and setting no collisions with the heat bath ({{TAG|ANDERSEN_PROB}}=0). | ||
*{{TAG|ISIF}}: This tag controls which type of ensemble is chosen (NVE,NVT or NPT). | *{{TAG|ISIF}}: This tag controls which type of ensemble is chosen (NVE,NVT or NPT). | ||
Revision as of 11:31, 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 thermostat used in the molecular dynamics calculations. For regular molecular dynamics calculations the thermostat is selected by a one digit number (e.g. 1 for Andersen, 2 for Nose-Hoover etc.). For biased molecular dynamics, metadynamics etc. the thermostat is selected by a two digit number where the first digit corresponds to the thermostat analogously to regular molecular dynamics and the second digit corresponds to the molecular dynamics type (e.g. 11 metadynamics with Andersen thermostat, 21 metadynamics with Nose-Hoover thermostat etc.). The NVE ensemble is a special case. It is available by selecting the Andersen thermostat and setting no collisions with the heat bath (ANDERSEN_PROB=0).
- ISIF: This tag controls which type of ensemble is chosen (NVE,NVT or NPT).
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