Hello dear Shyamvarnan Baskar

MolQube's specialized team can help you a lot. I think you should email them. [email protected]

Could you please clarify more?

I can not understand your question.

Dont know how to get binding energy from two cocrystals using BSSE calculation. So can you let me know if you know the input and analyze the output data? Prasanta Bandyopadhyay

I can tell you about BSSE calculation that we use for intermolecular interactions. If you use gaussian, there are numerous examples even in researchgate. If you use ORCA or PSI4 (free to use for academic purposes) have a look at these links,

https://sites.google.com/site/orcainputlibrary/useful-scripts-and-commands-for-orca-inputoutput

https://psicode.org/psi4manual/master/nbody.html

I will look into the links that you have suggested but now I'm mainly using gaussian. Thank you for your kind response. Prasanta Bandyopadhyay

With gaussian and Gview, it is fairly easy.

With Gview, go to edit -> atom groups and select the two molecules by atom numbers. Which actually creates two or more groups of atoms. roupsAfter that, go to calculate -> general and use counterpoise.

See if the charge and multiplicity of the total and fragment systems are al right, then you can run the calculation.

One sample example of CH4 dimer with HF/3-21G basis and counterpoise=2 is as,

%chk=adgf.chk

# hf/3-21g counterpoise=2

Title Card Required

0 1 0 1 0 1

C(Fragment=1) -5.70052551 -0.30647986 0.00000000

H(Fragment=1) -5.34387109 -1.31528986 0.00000000

H(Fragment=1) -5.34385267 0.19791833 0.87365150

H(Fragment=1) -5.34385267 0.19791833 -0.87365150

H(Fragment=1) -6.77052551 -0.30646667 0.00000000

C(Fragment=2) -0.72679511 0.00875657 0.00000000

H(Fragment=2) -0.37014069 -1.00005344 0.00000000

H(Fragment=2) -0.37012227 0.51315476 0.87365150

H(Fragment=2) -0.37012227 0.51315476 -0.87365150

H(Fragment=2) -1.79679511 0.00876975 0.00000000