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Redetermination of Nd2Ti2O7: a non-centrosymmetric structure with perovskite-type slabs.

ABSTRACT: Single crystals of dineodymium(III) dititanium(IV) hepta-oxide, Nd2Ti2O7, were synthesized by the flux method and found to belong to the family of compounds with perovskite-type structural motifs. The asymmetric unit contains four Nd, four Ti and 14 O-atom sites. The perovskite-type slabs are stacked parallel to (010) with a thickness corresponding to four corner-sharing TiO6 octa-hedra. The Nd and Ti ions are displaced from the geometrical centres of respective coordin-ation polyhedra so that the net polarization occurs along the c axis. The investigated crystals were all twinned and have a halved monoclinic unit cell in comparison with the first structure determination of this compound [Scheunemann & Müller-Buschbaum (1975 ?). J. Inorg. Nucl. Chem. 37, 2261-2263].

SUBMITTER: Ishizawa N

PROVIDER: S-EPMC3629463 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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Redetermination of Nd2Ti2O7: a non-centrosymmetric structure with perovskite-type slabs.

Ishizawa Nobuo N Ninomiya Keisuke K Sakakura Terutoshi T Wang Jun J

Acta crystallographica. Section E, Structure reports online 20130306 Pt 4

Single crystals of dineodymium(III) dititanium(IV) hepta-oxide, Nd2Ti2O7, were synthesized by the flux method and found to belong to the family of compounds with perovskite-type structural motifs. The asymmetric unit contains four Nd, four Ti and 14 O-atom sites. The perovskite-type slabs are stacked parallel to (010) with a thickness corresponding to four corner-sharing TiO6 octa-hedra. The Nd and Ti ions are displaced from the geometrical centres of respective coordin-ation polyhedra so that t ...[more]

PMID: 23633981

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