Section MD

• This section defines the whole set of parameters needed perform an MD run.

• Section path: CP2K_INPUT / MOTION / MD

• This section cannot be repeated and cannot be optional.

• Subsections

  • ADIABATIC_DYNAMICS
  • AVERAGES
  • BAROSTAT
  • CASCADE
  • LANGEVIN
  • MSST
  • PRINT
  • REFTRAJ
  • RESPA
  • SHELL
  • THERMAL_REGION
  • THERMOSTAT

• Keywords

  • ANGVEL_TOL
  • ANGVEL_ZERO
  • ANNEALING
  • ANNEALING_CELL
  • COMVEL_TOL
  • DISPLACEMENT_TOL
  • ECONS_START_VAL
  • ENSEMBLE
  • SCALE_TEMP_KIND
  • STEPS
  • STEP_START_VAL
  • TEMPERATURE
  • TEMP_KIND
  • TEMP_TOL
  • TIMESTEP
  • TIME_START_VAL

• Keyword descriptions

  ANGVEL_TOL
  	ANGVEL_TOL 0.1
  	The maximum accepted angular velocity. This option is ignored when the system is periodic. Removes the components of the velocities thatproject on the external rotational degrees of freedom.
  	This optional keyword cannot be repeated and it expects precisely one real.
  	Default unit: [au_t^-1bohr]

  ANGVEL_ZERO
  	ANGVEL_ZERO LOGICAL
  	Set the initial angular velocity to zero. This option is ignored when the system is periodic or when initial velocities are defined. Technically, the part of the random initial velocities that projects on the external rotational degrees of freedom is subtracted.
  	This optional keyword cannot be repeated and it expects precisely one logical.
  	The lone keyword behaves as a switch to .TRUE.
  	Default value: .FALSE.

  ANNEALING
  	ANNEALING <REAL>
  	Specifies the rescaling factor for annealing velocities. Automatically enables the annealing procedure. This scheme works only for ensembles that do not have thermostats on particles.
  	This optional keyword cannot be repeated and it expects precisely one real.
  	Default value: 1.00000000E+00

  ANNEALING_CELL
  	ANNEALING_CELL <REAL>
  	Specifies the rescaling factor for annealing velocities of the CELL Automatically enables the annealing procedure for the CELL. This scheme works only for ensambles that do not have thermostat on CELLS velocities.
  	This optional keyword cannot be repeated and it expects precisely one real.
  	Default value: 1.00000000E+00

  COMVEL_TOL
  	COMVEL_TOL 0.1
  	The maximum accepted velocity of the center of mass. With Shell-Model, comvel may drift if MD%THERMOSTAT%REGION /= GLOBAL
  	This optional keyword cannot be repeated and it expects precisely one real.
  	Default unit: [au_t^-1bohr]

  DISPLACEMENT_TOL
  	DISPLACEMENT_TOL <REAL>
  	This keyword sets a maximum atomic displacement in each Cartesian direction.The maximum velocity is evaluated and if it is too large to remainwithin the assigned limit, the time step is rescaled accordingly,and the first half step of the velocity verlet is repeated.
  	This optional keyword cannot be repeated and it expects precisely one real.
  	Default value: 5.29177209E+01
  	Default unit: [angstrom]

  ECONS_START_VAL
  	ECONS_START_VAL <REAL>
  	The starting value of the conserved quantity
  	This optional keyword cannot be repeated and it expects precisely one real.
  	Default value: 0.00000000E+00
  	Default unit: [hartree]

  ENSEMBLE
  	ENSEMBLE NVE
  	The ensemble/integrator that you want to use for MD propagation
  	This optional keyword cannot be repeated and it expects precisely one keyword.
  	Default value: NVE
  	List of valid keywords: HYDROSTATICSHOCK simulate steady shock with hydrostatic pressure ISOKIN constant kinetic energy LANGEVIN langevin dynamics (constant temperature) MSST simulate steady shock (uniaxial) MSST_DAMPED simulate steady shock (uniaxial) with extra viscosity NPE_F constant pressure ensemble (no thermostat) NPE_I constant pressure ensemble using an isotropic cell (no thermostat) NPT_F constant temperature and pressure using a flexible cell NPT_I constant temperature and pressure using an isotropic cell NVE constant energy (microcanonical) NVT constant temperature and volume (canonical) NVT_ADIABATIC adiabatic dynamics in constant temperature and volume ensemble REFTRAJ reading frames from a file called reftraj.xyz (e.g. for property calculation)
  	This keyword cites the following references: [EVANS1983] [Kolafa2004] [Minary2003]

  SCALE_TEMP_KIND
  	SCALE_TEMP_KIND LOGICAL
  	When necessary rescale the temperature per each kind separately
  	This optional keyword cannot be repeated and it expects precisely one logical.
  	The lone keyword behaves as a switch to .TRUE.
  	Default value: .FALSE.

  STEPS
  	STEPS 100
  	The number of MD steps to perform
  	This optional keyword cannot be repeated and it expects precisely one integer.
  	Default value: 3

  STEP_START_VAL
  	STEP_START_VAL <INTEGER>
  	The starting step value for the MD
  	This optional keyword cannot be repeated and it expects precisely one integer.
  	Default value: 0

  TEMPERATURE
  	TEMPERATURE 325.0
  	The temperature in K used to initialize the velocities with init and pos restart, and in the NPT/NVT simulations
  	This optional keyword cannot be repeated and it expects precisely one real.
  	Default value: 3.00000000E+02
  	Default unit: [K]

  TEMP_KIND
  	TEMP_KIND LOGICAL
  	Compute the temperature per each kind separately
  	This optional keyword cannot be repeated and it expects precisely one logical.
  	The lone keyword behaves as a switch to .TRUE.
  	Default value: .FALSE.

  TEMP_TOL
  	TEMP_TOL 0.0
  	The maximum accepted deviation of the (global) temperaturefrom the desired target temperature before a rescaling of the velocites is performed. If it is 0 no rescaling is performed. NOTE: This keyword is obsolescent; Using a CSVR thermostat with a short timeconstant is recommended as a better alternative.
  	This optional keyword cannot be repeated and it expects precisely one real.
  	Default value: 0.00000000E+00
  	Default unit: [K]
  	Alias names for this keyword: TEMP_TO, TEMPERATURE_TOLERANCE

  TIMESTEP
  	TIMESTEP 1.0
  	The length of an integration step (in case RESPA the large TIMESTEP)
  	This optional keyword cannot be repeated and it expects precisely one real.
  	Default value: 5.00000000E-01
  	Default unit: [fs]

  TIME_START_VAL
  	TIME_START_VAL <REAL>
  	The starting timer value for the MD
  	This optional keyword cannot be repeated and it expects precisely one real.
  	Default value: 0.00000000E+00
  	Default unit: [fs]