Chemical pressure induced spin reorientation in the magnetic structure of Ca 3 Mn 2-x Sn x O 7 (x = 0.03, 0.05)

• Published in: Journal of physics. Condensed matter Vol. 36; no. 43; p. 435801
• Main Authors: Mohan, Ashwin, Vaidya, Salil S, Jain, Anil K, Yusuf, S M
• Format: Journal Article
• Language: English
• Published: England 30.10.2024
• Subjects: magnetism; neutron diffraction; antiferromagnetism; hybrid improper ferroelectric; calcium manganate; octahedral distortion
• ISSN: 0953-8984; 1361-648X
• DOI: 10.1088/1361-648X/ad636d

The effect of partially substituting Tin (Sn) at the Manganese (Mn) site of Ca Mn O viz. Ca Mn Sn O with x = 0.03 and 0.05, on its structural and magnetic properties has been investigated using synchrotron diffraction, neutron diffraction, and bulk magnetization measurements. It is observed that with a substitution of only 3 at% Sn, the minor (≈ 8%) tetragonal ( ) structural phase that is present in the predominantly orthorhombic ( ) undoped Ca Mn O , completely disappears. The compounds order antiferromagnetically, the ordering temperature decreases with increasing Sn-content, and indicating a weakening of the antiferromagnetic exchange interactions. Interestingly, in the ordered state, the spin magnetic moments which were aligned along the -axis of the unit cell in the undoped compound, are observed to have reoriented with their major components lying in the plane in the Sn-doped compounds. The above influence of Sn-doping is seen to be stemming from a significant modification of the octahedral rotation and tilt mode geometry in the unit cell, that is known to be responsible for driving ferroelectricity in these compounds.