sp2graph.tb

Functions for solving a simple nearest neighbors tight-binding problem given by the hopping matrix (adjacency matrix).

sp2graph.tb.tbBondOrder(V, L=None, radius=1.6)

Computes the total bond order (BO) between pairs of neighboring atoms. Note that the hopping matrix elements in the electronic Hamiltonian are negative numbers as they represent the stabilization energy for electrons that are allowed to delocalize, i.e., \(H_{ij} < 0\). Currently the implementation handles periodic systems along a single dimension. It’s just a temporary implementation and should be changed after the introduction of a proper graph class.

Parameters:

V : array_like

List of vertices

L : array_like, optional

Lattice vectors

radius : float, optional

Range of neighbor interactions in Angstrom

Returns:

numpy.array

Bond order \(\mathrm{BO}_{ij}\) between all atom pairs i and j.