Dear Sir, Then how does the conductance graph differ between two honeycomb lattices..say for boron nitride nanoribbons and graphene nanoribbons? If it is atom independent then how does the I-V curve vary?
I do not believe I said anywhere that the conductance of a graphene nanoribbon and a Boron Nitride nanoribbon would be the same. What I said is that it is up to you, the user, to define *how* those two systems are different by supplying the onsites/hoppings that correspond to your physical model.
For you Boron Nitride example I guess that this would mean (at the very least) giving different onsite values to the sites that correspond to Boron and Nitrogen atoms. The numerical values that you actually assign (and whether a simple single-orbital model is even valid) will depend on what physical model you are using; Kwant does not come with any such models out of the box.
Hope that clarifies,