Formation of Ti3+ ions at the surface of laser-irradiated rutile

Sintered samples of rutile have been submitted to the irradiation of a 355 nm laser beam. X-ray absorption spectroscopy at the Ti K-edge and X-ray photoelectron spectroscopy provide evidence in favour of Ti3+ ion formation in the near-surface region of the samples. Structural information derived from the extended X-ray absorption fine structure and from electron spin resonance spectroscopy show that the laser irradiation does not alter the Ti local environment but affects the long-range order of the sample. This allows an understanding of the electrical properties observed for laser-irradiated rutile.