RSL2Potential

class RSL2Potential(particleType1, particleType2, a, b, c, r_cut=None)

Constructor of the potential.

Parameters:
  • particleType1 (ParticleType or ParticleIdentifier) – Identifier of the first particle type.
  • particleType2 (ParticleType or ParticleIdentifier) – Identifier of the second particle type.
  • a (PhysicalQuantity of type energy) – Potential parameter.
  • b (PhysicalQuantity of type length**-1) – Potential parameter.
  • c (PhysicalQuantity of type length) – Potential parameter.
  • r_cut (PhysicalQuantity of type length) – The cutoff radius of this potential.
getAllParameterNames()

Return the names of all used parameters as a list.

getAllParameters()

Return all parameters of this potential and their current values as a <parameterName / parameterValue> dictionary.

static getDefaults()

Get the default parameters of this potential and return them in form of a dictionary of <parameter name, default value> key-value pairs.

getParameter(parameterName)

Get the current value of the parameter parameterName.

setCutoff(r_cut)

Set the cutoff radius for this potential.

Parameters:r_cut (PhysicalQuantity of type length) – The cutoff radius of this potential.
setParameter(parameterName, value)

Set the parameter parameterName to the given value.

Parameters:
  • parameterName (str) – The name of the parameter that will be modified.
  • value – The new value that will be assigned to the parameter parameterName.
seta(a)

Set the parameter a.

Parameters:a (PhysicalQuantity of type energy) – Potential parameter.
setb(b)

Set the parameter b.

Parameters:b (PhysicalQuantity of type length**-1) – Potential parameter.
setc(c)

Set the parameter c.

Parameters:c (PhysicalQuantity of type length) – Potential parameter.

Notes

The revised central force potential of Stillinger and Rahman (RSL2) [SR78], defines an interaction of the form

\[V_{ij}(r) = \frac{a_{ij}}{1+\exp(b_{ij}(r - c_{ij}))} \,.\]

[SR78]F. H. Stillinger and A. Rahman. Revised central force potentials for water. J. Chem. Phys., 1978. doi:10.1063/1.435738.