The phase CrFeTi2O7 has been synthesized and is monoclinic, Å, b = 5.000(2)Å, c = 14.425(6)Å, β = 116.59(4)°. It is isostructural with the compound Cr2Ti2O7. The structure is based on distorted hexagonal close packing of oxygen atoms, with the metal atoms occupying particular octahedral interstices to give a complex arrangement of octahedra joined by the sharing of corners, edges and faces. For ... [Show full abstract] one of the metal atom sites in the structure there is a 15% disorder for which possible origins are discussed. CrFeTi2O7 is a member of the homologous series of compounds A2Bn−2O2n−1 (A = Cr, Fe; B = Ti, Zr) whose structures are closely related to that of α-PbO2, and may be considered to derive from it by the application of crystallographic shear.