8.5. Non-Bond Lennard-Jones Potential - AB Form (Two atom types)¶
8.5.1. Functional Form¶
The non-bond Lennard-Jones (AB Form) potential has the functional form:
\(E=\frac{{{A}_{ij}}}{R_{ij}^{12}}-\frac{{{B}_{ij}}}{R_{ij}^{6}}\)
The force-field parameters for this potential and units are given by:
Equation Symbol | Parameter Definition | Units |
\(A_{ij}\) | General 12th power Lennard-Jones coefficient [i] | energy*length^12/mol |
\(B_{ij}\) | General 6th power Lennard-Jones coefficient [i] | energy*length^6/mol |
8.5.2. XML Schema¶
The XML schema for the non-bond Lennard-Jones (AB Form) potential has the following representation (design mode representation using Liquid XML Studio):
The relationship between the equation symbols and XML schema notations are given by:
Parameter Definition | Equation Symbol | Schema Notation |
Atom type of atom [i] | (implicit) | AT-1 |
Atom type of atom [j] | (implicit) | AT-2 |
General 12th power Lennard-Jones coefficient [i] | \(A_{ij}\) | A |
General 6th power Lennard-Jones coefficient [i] | \(B_{ij}\) | B |
The general attributes (describing the entire data set) are given by:
General Attributes | Cardinality | Value/Definition |
style | Fixed | Lennard-Jones (12-6) [A-B Form] |
formula | Fixed | A/(R^12)-B/(R^6) |
A–units | Required | Enumerations specified in schema |
B-units | Required | Enumerations specified in schema |
The specific attributes (attached to each set of parameters) are given by:
Specific Attributes | Cardinality | Value/Definition |
comment | Optional | Comment attached to parameter set |
version | Optional | Version number of parameter set |
reference | Optional | Reference attached to parameter set |
Note that an XML document will be rejected from being entered into the WebFF database if a required attribute is left unspecified.