Calculate the Magnitude of Nonadiabatic Coupling

I'm in the great position to be able to calculate nonadiabatic couplings with TDDFT.


The result of such a calculation is a displacement for every atom in x, y and z.



```
  Atom         X              Y              Z
---------------------------------------------------
   1      -0.000000      -0.000000      -0.160841
  ...         ...            ...            ...
   N       0.000000      -0.000000       0.009654
---------------------------------------------------

```

How do I calculate the magnitude of that coupling?


(It would be great, if you'd be as tutorial-like as possible.)


