Bond Functions
Functional forms for bond interactions
Below are listed the interaction forms available for bonds within molecules, with energy and force equations provided in full. Parameters are listed in the input order expected by Dissolve.
Bond interaction between atoms $i$ and $j$, where the bond length is $r_{ij}$.
| Keyword | Parameters | Description |
|---|---|---|
Harmonic |
k$r_{eq}$ |
Simple harmonic bond strech $$ E_{ij} = \frac{1}{2} k (r_{ij} - r_{eq})^2 $$ $$ F_{ij} = -k (r_{ij} - r_{eq}) $$ |
EPSR |
C'$r_{eq}$ |
Harmonic bond weighted by the masses of the atoms - equivalent to that implemented in EPSR, where $ C’ = C/2$. $$ E_{ij} = C’ (r_{ij} - r_{eq})^2 / \omega $$ $$ F_{ij} = - 2 C’ (r_{ij} - r_{eq}) / \omega $$ $$ \omega = \frac{r_{eq}}{\sqrt{ \frac{m_i + m_j}{m_i m_j}}} $$ |