Single crystal X-ray diffraction studies on [(CH{sub 3}){sub n}NH{sub 4-n}]{sub 3}[Sb{sub 2}Cl{sub 9}] (n=2, 3) chloroantimonates(III) in their low-temperature ferroelectric phases-structures and phase transitions

• Published in: Journal of solid state chemistry Vol. 178; no. 7
• Main Authors: Bujak, Maciej, Angel, Ross J.
• Format: Journal Article
• Language: English
• Published: United States 15.07.2005
• Subjects: ANTIMONATES; INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; LAYERS; MONOCLINIC LATTICES; MONOCRYSTALS; PHASE TRANSFORMATIONS; SPACE GROUPS; TEMPERATURE RANGE 0013-0065 K; TEMPERATURE RANGE 0065-0273 K; X-RAY DIFFRACTION
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/j.jssc.2005.04.020

The structures of two ferroic chloroantimonates(III): [(CH{sub 3}){sub 2}NH{sub 2}]{sub 3}[Sb{sub 2}Cl{sub 9}] (DMACA) and [(CH{sub 3}){sub 3}NH]{sub 3}[Sb{sub 2}Cl{sub 9}] (TMACA) were determined in their low-temperature phases. The structure of DMACA was investigated at 100 and 15K, and TMACA at 15K. The structures consist of two-dimensional inorganic layers and organic cations bound together by the N(C)-H...Cl hydrogen bonds. All of the organic cations in both compounds at all studied temperatures are ordered. There is no indication of the structural phase transition in the structure of DMACA below 242K. The geometry and distortions of the [SbCl{sub 6}]{sup 3-} octahedra in both compounds is discussed. The monoclinic Pc space group was found for both compounds: DMACA a=9.3590(5), b=9.0097(4), c=14.1308(7)A, {beta}=95.229(4){sup o}, R{sub 1}=0.0240, wR{sub 2}=0.0491 and a=9.3132(4), b=9.0008(3), c=14.1088(5)A, {beta}=95.010(3){sup o}, R{sub 1}=0.0230, wR{sub 2}=0.0482 at 100 and 15K, respectively; TMACA a=9.8652(5), b=9.1129(4), c=15.0964(7)A, {beta}=89.988(4){sup o}, R{sub 1}=0.0239, wR{sub 2}=0.0611 at 15K.