Discovery at the Interface between Known Structure Types: The Layered Y ₁₀ Ni x Cu 1– x Ti ₄ O ₂₄ Family

High Resolution Image Download MS PowerPoint Slide During the exploration of the interface between the known structures of perovskite Y 2 NiTiO 6 and hexagonal layered Y 2 CuTiO 6, we have discovered the new phase Y 10 Ni x Cu 1– x Ti 4 O 24 ( x = 0, 0.5, 1). The structure of Y 10 CuTi 4 O 24 was solved by means of single-crystal X-ray diffraction, which revealed a layered monoclinic structure, with the space group C 2/ m, a = 12.2405(1), b = 5.8643(1), c = 7.1729(1) Å, β = 107.083(1)°. The structures of three Y 10 Ni x Cu 1– x Ti 4 O 24 ( x = 0, 0.5, 1) phases were also refined based on high-resolution powder X-ray diffraction data. Substitution of Cu for Ni causes only minor changes in lattice and atomic parameters. The new phase is related to known Y 5 Mo 2 O 12 -type structures with an extra atomic position occupied by Ni/Cu in the structure of Y 10 Ni x Cu 1– x Ti 4 O 24 ( x = 0, 0.5, 1). The high-resolution powder X-ray diffraction data revealed peak broadening for the reflections with l = 2 n + 1 corresponding to stacking faults originating from the layered structure of Y 10 Ni x Cu 1– x Ti 4 O 24 . Y 10 Ni x Cu 1– x Ti 4 O 24 ( x = 0, 0.5, 1) were characterized with respect to their magnetic and optical properties.