Figure 1 illustrates the X-ray Photoelectron Spectra of the Ti 2p lines for a sample of TiO₂. The Binding Energy for the 2p3/2line is at 458.9 eV.

1. Explain, using appropriate diagrams, how the photoelectrons are generated in X-ray Photoelectron Spectra.
2. Giving your reasoning, state how the positions and relative intensities of the Ti 2p line would change if the spectra were of Ti metal rather than TiO₂. 
3. What is the origin of the second line at 464.7 eV?

458.9 ev 464.7 ev 40 0 404 42 0 Binding Energy (ov) 456 454 (ne sunoo