Raman spectroscopic study of the structural properties of CaO–MgO–SiO2–TiO2 slags

Raman spectra of CaO–MgO–SiO2–TiO2 slags were carefully analyzed to obtain the effect of TiO2 on the slag structures and the results are important for a better understanding of the behaviors of Ti-bearing slags. Gaussian deconvolutions of the Raman curves provide us with a deep insight into various structural units of the slags. The silicate network was more polymerized because of the increase of TiO2. Q2 (silica tetrahedra with two bridging oxygens) and Q3 species increase at the cost of Q0 and Q1 species. A significant fraction of Ti4 + plays the role of network formers and enters the silicate network, while some other Ti4 + exist in the slags in the form of TiO44 − monomers suggested by ~ 790 cm− 1 bands. A small content of 6-coordinated Ti4 + occurs when the fraction of TiO2 is relatively high. 5-Coordinated Ti4 + indicated by 870 cm− 1 may also appear and help the initial addition of Ti4 + into silicate network.