Dear Yambo Developers,

I am parameterizing a tight-binding hamiltonian. The system is a polymer on top of graphene.

I did the electronic structure with QuantumEspresso and I interpolated the band structure with Wannier90.

I have the 1-body part of the Hamiltonian in the Wannier basis set, namely <i|H|j> where i and j are Wannier Functions.

I also have the WannierFunctions in real space.

Now, I want to include the 2-body part of the Hamiltonian to get parameters concerning the exciton (e.g. binding energy).

So, I would like to calculate with Yambo the four center integrals in the Wannier basis set: <i j|e^2/r| k l> where i,j,k,l are WannierFunctions.

The important point here is that the coulomb matrix elements must be in the Wannier function basis set.

Is there an easy way to do that with Yambo?

I don't mind to modify the code to get the matrix elements that I need.

Thanks in advance,

Angelo Ziletti

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angelo.ziletti@gmail.com

Phd candidate

School of Physics

UCD - University College Dublin