New force field implantation for ONIOM(QM:MM)

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New force field implantation for ONIOM(QM:MM):

• REMEMBER; all ONIOM calculations should contain the connectivity and the atom types correctly set up (as in MM calculations). And should be the same for all species you wish to compare

• Partial charges for AMBER and ONIOM calculations can be generated in a couple of different ways.

1) For known AMBER residues, GaussView will generate the standard charges and supply them in the input file.

2) For non-standard AMBER residues no charge will be generated but you can use AMBER=QEq and use the charge equilibration method of Rappe and Goddard developed for UFF.

3) You can generate charges from a single point calculation with Pop=MK. For example LSDA/3-21G or HF/6-31G(d) depending on the size of your system. Then get charges either from the Mulliken analysis or the electrostatic potential fitting. You will need to supply these manually in the input.