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## Ensemble

- `Nose_thermostat <temp> <relax.time>`

  Specify whether to use the Nose thermostat. The option is incompatible with ``velocity scaling''. Two parameters are compulsory:

  `<temp>` - target temperature

  `<relax.time>` - relaxation time in femtoseconds

  Note: if simulation is restarted from a restart file, the old value of temperature specified in the restart file is normally used, ignoring value of this keyword. To override this, use keyword `Change_T`.

- `Velocity_scaling <temp> <dt>`

  Specify whether the temperature is regulated by the velocity scaling. The option is incompatible with ``Nose thermostat''. Two parameters are compulsory:

  `<temp>` - target temperature

  `<dt>` - admissible deviation. If the temperature deviates from the target by more that ``dt'', velocities are rescaled to fit the target temperature.

  Note: if simulation is restarted from a restart file, the old value of temperature specified in the restart file is normally used, ignoring value of this keyword. To override this, use keyword `Change_T` .

- `Separate_thermostating yes/no`

  Specify whether to apply temperature control to the whole system (no) or separately to each molecular type (yes). The option works both for Nose thermostate and for temperature control by velocity scaling

  default: no

  Note. At this option, the total momentum is not conserved. Use with care. See also `COM_check` keyword.

- `COM_check yes/no [num]`

  Specify whether to remove motion of the total center of mass. If parameter ``num'' is zero or negative, motion of the center of mass is removed only at the program start. If this parameter is positive, it gives the number of MD-steps after which the removal of center of mass motion is repeated

  Default: yes 0

- `Barostate_NH <pres> <relax_time>`

  Specify whether to use the Nose-Hoover barostate. Option works only if Nose thermostat is specified. Without the keyword, constant volume simulations are implied. Two parameters are compulsory:

  `<pres>` - pressure in bar (atm)

  `<relax_time>` - relaxation time in femtoseconds

- `Barostate_anisotropic yes/no`

  Specify whether to apply pressure control isotropically (no) or separately to each direction (yes). The option has effect only if constant-pressure simulations (barostate) is specified

  default: no

Next: Molecular Dynamics Up: The main input file Previous: System