Sphere¶

class hoomd.hpmc.integrate.Sphere(default_d=0.1, default_a=0.1, translation_move_probability=0.5, nselect=4, kT=1.0)¶

Bases: HPMCIntegrator

Sphere hard particle Monte Carlo integrator.

Parameters:

default_d (float) – Default maximum size of displacement trial moves \([\mathrm{length}]\).
default_a (float) – Default maximum size of rotation trial moves \([\mathrm{dimensionless}]\).
translation_move_probability (float) – Fraction of moves that are translation moves.
nselect (int) – Number of trial moves to perform per particle per timestep.
kT (hoomd.variant.variant_like) – Temperature set point \([\mathrm{energy}]\).

Perform hard particle Monte Carlo of spheres. The shape \(S\) includes all points inside and on the surface of a sphere:

\[S = \left \{ \vec{r} : \frac{\vec{r}\cdot\vec{r}}{(d/2)^2} \le 1 \right\}\]

where \(d\), is the diameter set in shape. When the shape parameter orientable is False (the default), Sphere only applies translation trial moves and ignores translation_move_probability.

Tip

Use spheres with diameter=0 in conjunction with pair potentials for Monte Carlo simulations of particles with no hard core.

Tip

Use Sphere in a 2D simulation to perform Monte Carlo on hard disks.

Wall support.

Sphere supports all hoomd.wall geometries.

Examples:

mc = hoomd.hpmc.integrate.Sphere(default_d=0.3, default_a=0.4)
mc.shape["A"] = dict(diameter=1.0)
mc.shape["B"] = dict(diameter=2.0)
mc.shape["C"] = dict(diameter=1.0, orientable=True)
print("diameter = ", mc.shape["A"]["diameter"])

Members inherited from AutotunedObject:

property kernel_parameters¶: Kernel parameters. Read more...

property is_tuning_complete¶: Check if kernel parameter tuning is complete. Read more...

tune_kernel_parameters()¶: Start tuning kernel parameters. Read more...

Members inherited from HPMCIntegrator:

a¶: Maximum size of the rotation trial moves. Read more...

d¶: Maximum size of displacement trial moves Read more...

interaction_matrix¶: Set which types interact with other types. Read more...

translation_move_probability¶: Fraction of moves to be selected as translation moves. Read more...

nselect¶: Number of trial moves to perform per particle per timestep. Read more...

kT¶: Temperature set point. Read more...

property counters¶: Trial move counters. Read more...

property external_energy¶: Total external energy contributed by all external potentials. Read more...

property external_potentials¶: External potentials to apply. Read more...

property map_overlaps¶: List of overlapping particles. Read more...

property mps¶: Number of trial moves performed per second. Read more...

property overlaps¶: Number of overlapping particle pairs. Read more...

property pair_energy¶: Total potential energy contributed by all pair potentials. Read more...

property pair_potentials¶: Pair potentials to apply. Read more...

property rotate_moves¶: Count of the accepted and rejected rotate moves. Read more...

property translate_moves¶: Count of the accepted and rejected translate moves. Read more...

Members defined in Sphere:

shape¶

The shape parameters for each particle type. The dictionary has the following keys:

diameter (float, required) - Sphere diameter \([\mathrm{length}]\).
ignore_statistics (bool, default: False) - set to True to ignore tracked statistics.
orientable (bool, default: False) - set to True to allow rotation moves on this particle type.

Type:: TypeParameter [particle type, dict]

property type_shapes¶

Description of shapes in type_shapes format.

Examples

The types will be ‘Sphere’ regardless of dimensionality.

>>> mc.type_shapes
[{'type': 'Sphere', 'diameter': 1},
 {'type': 'Sphere', 'diameter': 2}]

(Loggable: category=”object”)

Type:: list[dict]