Optical phonon self-energies in titanium phases: effects of electron–phonon interaction

Temperature-dependent Raman investigations of titanium in the α and pressure-quenched ω-phase have been carried out. The results obtained suggest the possible coexistence of both phases at ambient pressure and low temperatures. Comparison of the low-temperature E2g phonon self-energies in both phases with simulations based on the calculated electronic structures for α- and ω-Ti implies significant contributions from non-adiabatic electron–phonon interactions.