Dimer energy with give charge distribution?
I want to calculate the pair interaction energy as a function of dimer distance while not allowing the electron density of isolated atoms to relax. That means each atom has the charge distribution like a isolated atom and put 2 of them in a box and read the energy. Is that possible? How should I do it? Thank you!
Are you looking just for a Coulomb interaction energy?
The SAPT method gives you that and more http://www.physics.udel.edu/~szalewic/SAPT/SAPT.html (but interfacing other programs than ELK).
Thank you for the answer.
The question is how to set the charge distribution in the dimer as the simple addition of two "isolated" atoms.