[CPMD-list] How accurate is the energy calculation of charged systems?

[liu liuxiandong]

Dear CPMDers and Axel,

  For example, in the box, an ammonium group (NH4 (+)) is hydrated by 64
water molecules. The total energy of this system is denoted as E1 (after
relaxation and calculated with setting CHARGE=1). Then the isolated ammonium
group and the 64 water molecules in the box of the same dimensions are
cauculated and noted as E2 (under CHARGE=1) and E3. Then, can I estimate the
hydration energy of the ammonium group from (E2+E3-E1) ?
  Thanks for any suggestions.



  BEST,
Xiandong Liu
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://cpmd.org/pipermail/cpmd-list/attachments/20071022/c5655a47/attachment.html