Valence-band splitting of SrTiO3

Optical charge-transfer transitions from the oxygen valence bands to Fe5+ and V5+ impurity states at Ti4+ sites in SrTiO3 reveal a 0.42-eV valence-band splitting. Since these transitions are observed with conventional optical-absorption spectroscopy, their resolution is far better than previously obtained by photoelectron spectroscopy. © 1983 The American Physical Society.