Harmonic

class hoomd.md.improper.Harmonic

Bases: Improper

Harmonic improper force.

Harmonic computes forces, virials, and energies on all impropers in the simulation state with:

$$U(r) = \frac{1}{2}k \left( \chi - \chi_{0} \right )^2$$

Example:

harmonic = hoomd.md.improper.Harmonic()
harmonic.params["A-B-C-D"] = dict(k=1.0, chi0=0)

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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...

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Members inherited from Force:

additional_energy

Additional energy term. Read more...

additional_virial

Additional virial tensor term $W_\mathrm{additional}$. Read more...

cpu_local_force_arrays

Local force arrays on the CPU. Read more...

energies

Energy contribution $U_i$ from each particle. Read more...

energy

The potential energy $U$ of the system from this force. Read more...

forces

The force $\vec{F}_i$ applied to each particle. Read more...

gpu_local_force_arrays

Local force arrays on the GPU. Read more...

torques

The torque $\vec{\tau}_i$ applied to each particle. Read more...

virials

Virial tensor contribution $W_i$ from each particle. Read more...

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Members defined in Harmonic:

params

The parameter of the harmonic impropers for each improper type. The dictionary has the following keys:

• k (float, required), potential constant $k$ $[\mathrm{energy}]$.

• chi0 (float, required), equilibrium angle $\chi_0$ $[\mathrm{radian}]$.

Type:

TypeParameter [improper type, dict]