Peach, M. J., Teale, A. M., Helgaker, T., & Tozer, D. J. (2015). Fractional Electron Loss in Approximate DFT and Hartree–Fock Theory. Journal of Chemical Theory and Computation, 11(11), 5262-5268. https://doi.org/10.1021/acs.jctc.5b00804