## Fundamental on potential term
Before investigating the specific expression of potentials. One should be familiar with typical values of them.
| **Non-covalent** | energy (kcal/mol) | **Covalent** | energy (kcal/mol) |
|:------------------------------------------:|:-----------------:|--------------|-------------------|
| Hydrophobic | <10 | C-O | 81 |
| Electrostatic | 1-20 | C-C | 86 |
| Hydrogen bond | 2-30 | C-H | 103 |
| Stacking of aromatic molecules ($\pi-\pi$) | 0-10 | C=C | 143 |
| VdW | 0.1-1 | C=O | 165 |
And for potential $V$, the force is $F(R) = -\frac{\mathrm{d} V(R)}{\mathrm{d} R}$.
>[!Notice]
>1 Ha = 17.211 eV =627.5 kcal/mol
>1eV = 23 kcal/mol
>
> And one should notice that provisions bonds are much larger (x100) than VdW.
>[!Infor]
>See more on other notes about potential: [[Potential, force, momentum, velocity]], [[Expression for potential terms]].