[Rdkit-discuss] Listing all UFF torsion parameters present in a molecule (V_jk, n_jk, phi0_jk)

[Francois B. <ml...@li...>]

Dear rdkiters,

Is it possible to list all the torsion angles UFF parameters
around single bonds out of rings (rotatable bonds) for a given molecule 
?

 From what I found in the rdkit doc, it is (only?) possible to extract
the Vjk value for four consecutive atoms indexed i j k l.

But, Vjk is just one parameter (the torsion barrier in kcal/mol): for 
each torsion angle
UFF also defines the multiplicity of the barrier (n_jk, an integer) and 
phi0
(the angle in degrees at which the barrier is 0), if I understand 
correctly.

I am reading carefully the DREIDING and UFF papers, but I am not (yet?)
sure I will be able to get that correctly.
So, since rdkit has an UFF implementation, I wonder if it would not
be safer to have just rdkit list for me all those torsions parameters 
for the molecule at hand.

If rdkit cannot do that, I might post later a tentative solution so that 
another pair
of eyes might tell me if I got this correctly.

Regards,
F.