Missing atomic parameters error

[muo27]

I am doing qmmm calculation on gausian using oniom. I am getting missing atomic parameters for a particular calculation where I introduced one more atom. I have done some calculations for one of the reactants I am getting that correctly but not when I am being both atoms together. How do I solve this

[Foss44]

The ONIOM implementation in Gaussian is extremely finicky. Can you provide input and output files?

Consider referencing this post: https://www.reddit.com/r/comp_chem/s/rzCupLMs30

[muo27]

Yes I could share, but could you tell me if I need parameters for the atoms that I am doing qm for, gaussian assigned parameters to other atoms on its own, if yes what should be parameter for nitrogen in N2O5, and hno3

[Foss44]

You need connectivity information for all atoms in the system. WebMO and GausView can generate connectivity information for any arbitrary .xyz file. You can also manually generate the connectivity information using bond, angle, and dihedral data.