"114"‐Type Nitrides LnAl(Si4−xAlx)N7Oδ with Unusual [AlN6] Octahedral Coordination. (28th February 2017)

• Record Type: Journal Article
• Authors: Huang, Saifang; Huang, Zhaohui; Cao, Peng; Zujovic, Zoran; Price, Jason R.; Avdeev, Maxim; Que, Meidan; Suzuki, Furitsu; Kido, Tsuyoshi; Ouyang, Xin; Kaji, Hironori; Fang, Minghao; Liu, Yan‐gai; Gao, Wei; Söhnel, Tilo
• Is Part Of: Angewandte Chemie. Volume 129:Number 14(2017)
• Page Start: 3944
• Page End: 3949
• Publication Date: 2017-02-28
• Subjects: Aluminium -- [AlN6]-Oktaeder -- Nitride -- NMR-Spektroskopie -- Strukturaufklärung; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201612488
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Aluminum–nitrogen six‐fold octahedral coordination, [AlN6 ], is unusual and has only been seen in the high‐pressure rocksalt‐type aluminum nitride or some complex compounds. Herein we report novel nitrides LnAl(Si4− x Alx )N7 O δ (Ln=La, Sm), the first inorganic compounds with [AlN6 ] coordination prepared via non‐high‐pressure synthesis. Structure refinements of neutron powder diffraction and single‐crystal X‐ray diffraction data show that these compounds crystallize in the hexagonal Swedenborgite structure type with P 63 mc symmetry where Ln and Al atoms locate in anticuboctahedral and octahedral interstitials, respectively, between the triangular and Kagomé layers of [SiN4 ] tetrahedra. Solid‐state NMR data of high‐purity La‐114 powders confirm the unusual [AlN6 ] coordination. These compounds are the first examples of the "33‐114" sub‐type in the "114" family. The additional site for over‐stoichiometric oxygen in the structure of 114‐type compounds was also identified.