A systematic study of the Raman spectra of the titanomagnetite solid-solution series (Fe3–xTixO4) for x = ~0.0, 0.2, 0.4, and 0.6 has been conducted. The samples showed combinations of five previously predicted Raman peaks at ~190, 310, 460, 540, and 670 cm−1 that correspond to vibrational modes with T2g(1), Eg, T2g(3), T2g(2), and A1g, respectively. The calibration of Raman spectra for titanomagnetite with known values of Ti concentrations reveals a strong dependence of relative intensity for the T2g(2) and T2g(3) modes on Ti concentration. The most prominent feature is the appearance and increase in the relative intensity of a T2g(3) peak above x = ~0.2. On the other hand, the Raman peak for the T2g(2) mode gradually diminishes as Ti increases and nearly disappears at x = ~0.6. Combining the two relative intensities potentially provides a sensitive indicator of Ti content. The technique was applied to study titanomagnetite in grains from Hana Volcanics and melatroctolite from Rhode Island.

You do not currently have access to this article.