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Structural Studies of CaAl12O19, SrAl12O19, La2/3+δAld12-δO19, and CaAl10NiTiO19 with the Hibonite Structure; Indications of an Unusual Type of Ferroelectric
Published
Author(s)
Jun Li, Elena A. Medina, Judith K. Stalick, Arthur W. Sleight, M. A. Subramanian
Abstract
Various oxides with the hibonite structure were synthesized and structurally analyzed using powder neutron diffraction. The structure of CaAl12O19 at 298 K and 11 K shows dipoles that are apparently too dilute to order unless subjected to a suitable electric field. Magnetoplumbites, such as BaFe12O19, are isostructural with hibonite. These compounds possess ferromagnetic properties, which combined with the electric dipoles may influence multiferroic behavior. Our SrAl12O19 sample showed two distinct hexagonal phases, a major phase with the normal hibonite structure and a minor phase having a closely related structure. Our sample of the defect hibonite La2/3+δAld12-δO19 phase shows a distinctly higher δ value (0.25) vs that reported (0.15) for samples made from the melt. Finally, we used to advantage the negative scattering length of Ti to determine the site occupancies of Ni Nd Ti in CaAl10NiTiO19.
Citation
Zeitschrift Fur Naturforschung Section B-A Journal of Chemical Sciences
Li, J.
, Medina, E.
, Stalick, J.
, Sleight, A.
and Subramanian, M.
(2016),
Structural Studies of CaAl<sub>12</sub>O<sub>19</sub>, SrAl<sub>12</sub>O<sub>19</sub>, La<sub>2/3+δAl</sub>d12-δO<sub>19</sub>, and CaAl<sub>10</sub>NiTiO<sub>19</sub> with the Hibonite Structure; Indications of an Unusual Type of Ferroelectric, Zeitschrift Fur Naturforschung Section B-A Journal of Chemical Sciences, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=920123
(Accessed October 10, 2025)