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Validation of calculated total energy (Read 2777 times)
Gerrit-Jan Linker
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Validation of calculated total energy
03.09.08 at 12:59:53
 
Validation of calculated total energy
 
The total energy as calculated using various methods (HF, RASSCF, etc) can be validated by considering the sum of the atomic energies. Using the same basisset ideally the atomic energies can be calculated. Summing the energies for the various atoms present in the molecule serves as an estimate for the total energy. It should not be hundreds of hartrees different from the calculated total Energy.
 
Differences in total energy between various calculation methods can arise when not the same total energies are compared. Perhaps not all the contributions are always included: e.g. nuclear repulsion, elecron repulsion, electron nucleus attraction.
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Gerrit-Jan Linker
Linker IT Software
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Gerrit-Jan Linker
YaBB Administrator
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Posts: 75
RASSCF atomic energies
Reply #1 - 04.09.08 at 07:26:05
 
RASSCF atomic energies
 
Atomic total energies calculated with RASSCF.  
 
AtomEnergy (a.u.)
C-37.58855791
H-0.49823291
O-74.65660411
S-397.39272704

 
For all calculations the 6-31G** basisset was used
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« Last Edit: 04.09.08 at 07:28:53 by Gerrit-Jan Linker »  

Gerrit-Jan Linker
Linker IT Software
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