  The study on the electronic state of muon as pseudo-hydrogen (represented by
the elemental symbol Mu) has long been appreciated as one of the few methods to
experimentally access the electronic state of dilute hydrogen (H) in
semiconductors and dielectrics. Meanwhile, theoretical predictions on the
electronic state of H in these materials by first-principles calculations using
density functional theory (DFT) do not always agree with the observed states of
Mu, standing as an obstacle to integrating the findings of both Mu and H. In
this paper, we provide resolution to this problem by a semi-quantitative model
that enables systematic understanding of the electronic states of Mu in most
oxides.
