The input file on gamess (generated from Avogadro) let me choose the charge and multiplicity of a single molecule, so for a single anion or cation, it is okay and I can run any calculation.
But for a paired (C+;A-) drawn on Avogadro (so, a neutral entity), I am not sure that the positive and negative charges are present on the corresponding cation and anion since avogadro don't let me this possibility to add charge on specific atoms. (I am running Avogadro v.1.1.1).
Hello Pierre,
There is an option to put the charge in Avogadro. The only think is that it isn't necessary to specify charge in avogadro because it don't appear in gamess input. In the other hand, the important point to indicate charge is in the gamess input for know if you have a open or closed shell. Think that say that an "atom have a charge of -1, i.e. " it is an approximation for study, but not a real charge. In the case of C+ and A- the important is specify in input, not in avogadro. Maybe it will be important if you use a pre-optimization with UFF.
I am sorry, I do not know. Try to put the question on the Google GAMESS group: http://groups.google.com/group/gamess?hl=en.
Good luck,
V.
Hello Pierre,
There is an option to put the charge in Avogadro. The only think is that it isn't necessary to specify charge in avogadro because it don't appear in gamess input. In the other hand, the important point to indicate charge is in the gamess input for know if you have a open or closed shell. Think that say that an "atom have a charge of -1, i.e. " it is an approximation for study, but not a real charge. In the case of C+ and A- the important is specify in input, not in avogadro. Maybe it will be important if you use a pre-optimization with UFF.
You don't put the charge atom by atom in the input file, it is a result of the calculations. You should just input the total charge of your system: GAMESS should be able to calculate the charge distribution. That is, you should just put the two ions and give the total charge as an input (zero) and GAMESS will return how is it distributed between the two (+0.9 and -0.9 or something like that...).
dear Fernando and Joaquim,
Thanks a lot for your replies !
best regards,
- Badges
- Science topic