Some equations (just to show how to type equations)ΒΆ

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:

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