This Letter deals with the application of the virial and Hellmann-Feynman theorems to the Hermitian squared Hamiltonian characterizing the generalized version of the q-symmetrized Harper equation. This results in links between energy-eigenvalues and certain averages of selected Hamiltonian-terms, as usual. © 2003 Elsevier B.V. All rights reserved.
Micu, C., & Papp, E. (2003). Applying the virial and Hellmann-Feynman theorems to the generalized q-symmetrized Harper equation. Physics Letters, Section A: General, Atomic and Solid State Physics, 314(1–2), 10–14. https://doi.org/10.1016/S0375-9601(03)00861-2