[Wien] Formation energy + some other querries!

[Stefaan Cottenier]

> Also, just to confirm what Stefaan has said, if one does an atomic
> calculation for H, the total energy evaluated should be around 1Ryd?

In principle yes. But in practice it can be considerably off, due to  
using LDA/GGA instead of the exact XC functional. It would be a nice  
exercise to do this.

About N: its standard state is the N2 molecule, and this you can treat  
in a big empty cell just as for a free atom. However -- and that is  
what Chandrika referred to -- this will not involve vibrational energy  
of the molecule. Probably you can find such information elsewhere,  
such that you still have a meaningful value for N2.

Stefaan

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