sponge.function.VelocityGenerator

class sponge.function.VelocityGenerator(temperature: float = 300, remove_translation: bool = True, seed: int = 0, seed2: int = 0, length_unit: str = None, energy_unit: str = None)

A class to generate velocities for atoms in system according to temperature

Parameters

• temperature (float) – Temperature

• remove_translation (bool) – Whether to calculate distance under periodic boundary condition. Default: True

• seed (int) – Random seed for standard normal. Default: 0

• seed2 (int) – Random seed2 for standard normal. Default: 0

• length_unit (str) – Length unit. Default: None

• energy_unit (str) – energy unit. Default: None

Examples

>>> from sponge import UpdaterMD
>>> from sponge.function import VelocityGenerator
>>> vgen = VelocityGenerator(300)
>>> velocity = vgen(system.shape, system.atom_mass)
>>> opt = UpdaterMD(system=system,
...                 time_step=1e-3,
...                 velocity=velocity,
...                 integrator='velocity_verlet',
...                 temperature=300,
...                 thermostat='langevin')

set_temperature(temperature: float)

set temperature.

Parameters

temperature (float) – temperature