8.12. Tabular Non-Bond¶
8.12.1. Tabular Form¶
The tabular non-bond potential has the parameters:
| Parameter | Parameter Definition | Units |
| N | Number of tabulated values | N/A |
| R | Interatomic distance (least: rlo, greatest: rhi) | length |
| RSQ | Interatomic distance squared (least: rlo, greatest: rhi) | length^2 |
| BITMAP | Determines ordering of tabulated values (least: rlo, greatest: rhi) | length |
| FPRIME | Derivatives of the force at the innermost (fplo) and outermost (fphi) bond lengths | force/length length^2 |
The tabular non-bond potential has the tabulated values:
| index | r | energy | force |
| i_1 | r_1 | e_1 | f_1 |
| … | … | … | … |
| i_N | r_N | e_n | f_N |
8.12.2. XML Schema¶
The XML schema for the tabular non-ond potential has the following representation (design mode representation using Liquid XML Studio):
The relationship between the parameters/symbols and XML schema notations are given by:
| Parameter Definition | Parameter/Symbol | Schema Notation |
| Atom type of atom [i] | \(i\) | AT-1 |
| Atom type of atom [j] | \(j\) | AT-2 |
| Section identifying keyword | N/A | keyword |
| Number of tabulated values | N | N |
| Interatomic distance (least) | R | rlo |
| Interatomic distance (greatest) | R | rhi |
| Interatomic distance squared (least) | RSQ | rlo |
| Interatomic distance squared (greatest) | RSQ | rhi |
| Determines ordering of tabulated values (least) | BITMAP | rlo |
| Determines ordering of tabulated values (greatest) | BITMAP | rhi |
| Derivative of the force at the innermost | FPRIME | fplo |
| Derivative of the force at the outermost | FPRIME | fphi |
| Index | index | index |
| Interatomic distance | r | r |
| Energy | energy | energy |
| Force | force | force |
The general attributes (describing the entire data set) are given by:
| General Attributes | Cardinality | Value/Definition |
| style | Fixed | Tabular |
| Interpolation-style | Required | Enumerations specified in schema |
| r-units | Required | Enumerations specified in schema |
| energy-units | Required | Enumerations specified in schema |
| force-units | Required | Enumerations specified in schema |
| 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.