Thumbnail
Access Restriction
Open

Author Hinatsu, Yukio ♦ Doi, Yoshihiro
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY ♦ ANTIFERROMAGNETISM ♦ ANTIMONATES ♦ CRYSTALLOGRAPHY ♦ ENTROPY ♦ FLUORITE ♦ MAGNETIC SPECIFIC HEAT ♦ MAGNETIC SUSCEPTIBILITY ♦ ORTHORHOMBIC LATTICES ♦ OXIDES ♦ PHASE TRANSFORMATIONS ♦ SPACE GROUPS ♦ TEMPERATURE DEPENDENCE ♦ TERBIUM IONS ♦ X-RAY DIFFRACTION
Abstract Ternary rare-earth antimonates Ln{sub 3}SbO{sub 7} (Ln=rare earths) were prepared, and their structures were determined by X-ray diffraction measurements. They crystallize in an orthorhombic superstructure of cubic fluorite (space group Cmcm for Ln=La, Pr; Ccmm for Ln=Sm–Dy), in which Ln{sup 3+} ions occupy two different crystallographic sites (the 8-coordinated and 7-coordinated). For Ln=Nd, two phases with the Cmcm and Ccmm space groups coexist at room temperature. When the temperature was increased, the Nd{sub 3}SbO{sub 7} compound transformed into a single phase with the space group Cmcm. Through magnetic susceptibility measurements, an antiferromagnetic transition was observed at 3.0 K (Ln=Nd) and 7.8 K (Ln=Tb). Analysis of the magnetic specific heat for Tb{sub 3}SbO{sub 7} indicates that the 8-coordinated Tb ions magnetically orders at 7.8 K, and with furthermore decreasing temperature, the 7-coordinated Tb ions shows antiferromagnetic ordering at 3.0 K. - Graphical abstract: Temperature dependence of the specific heat divided by temperature (C{sub p}/T) and the magnetic entropy (S{sub mag}) for Tb{sub 3}SbO{sub 7}. Two-step magnetic transition has been observed. - Highlights: • The phase transition of Nd{sub 3}SbO{sub 7} is from the Ccmm space group to the Cmcm one. • Nd{sub 3}SbO{sub 7} shows an antiferromagnetic transition at 3.0 K. • For Tb{sub 3}SbO{sub 7}, two-step magnetic transition has been observed at 7.8 and 3.0 K.
ISSN 00224596
Educational Use Research
Learning Resource Type Article
Publisher Date 2014-09-15
Publisher Place United States
Journal Journal of Solid State Chemistry
Volume Number 217


Open content in new tab

   Open content in new tab