# Some equations (just to show how to type equations)¶

Example ...

$H = \sum_i h (i) + \frac{1}{2} \sum_{i \ne j} g (i, j) + V_{NN}; \quad V_{NN} = \frac{1}{2} \sum_{A \ne B} \frac{Z_A Z_B}{R_{AB}}$

Here is some inline example: $$V_{eN}$$. And another example:

$h_D = \beta mc^2 + c (\alpha \cdot \mathbf{p} ) + V_{eN}$

And yet another example:

$g^{Coulomb} (1, 2) = \frac{1}{r_{12}}$