Interestingly, NiTiO3 ilmenite can form continuous solid solutions with other M2+TiIVO3 titanates of Mg, Mn and Zn. For instance, cationic substitutions for Mg in MgTiO3 using divalent cations (like Ni2+, Co2+, Mn2+ or Zn2+) have been investigated from a crystallographic point of view [19,40,41] or aiming to improve their dielectric properties [29].