The two-center one-electron integral H_μν  

Sometimes called the resonance integral, H_μν is approximated using the overlap integral, S_μν. Note that this violates the NDO approximation, but since resonance integrals are large, this integral is retained. This is the origin of Modified in the name of the method. With Slater atomic orbitals of type

ψ_μ  = Nr^n-1e^-xr

the overlap integral is given by:

S_μν= <ψ_μψ_μ>

H_μνis approximated by:

H_μν = S_μν½ (β_μ β_μ)