vibeqc.mayer_bond_orders¶
- vibeqc.mayer_bond_orders(result, basis, molecule)[source]¶
Mayer bond-order matrix, shape (n_atoms, n_atoms).
For closed-shell systems:
B_AB = Σ_{μ ∈ A} Σ_{ν ∈ B} (P·S)_μν · (P·S)_νμ
For UHF / UKS we replace (P·S)(P·S) with the spin-resolved definition 2·[(Pα·S)(Pα·S) + (Pβ·S)(Pβ·S)] which reduces to the closed-shell formula when Pα = Pβ = P/2.
Diagonal entries are the “free valence” of each atom. The off- diagonals are the chemically-meaningful bond orders.
- Parameters:
basis (vibeqc._vibeqc_core.BasisSet)
molecule (vibeqc._vibeqc_core.Molecule)
- Return type: