resumo
GdFeTeO6 and GdGaTeO6 have been prepared and their structures refined by the Rietveld method. Both are superstructures of the rosiaite type (space group P3 over bar 1c). Their thermodynamic properties have been investigated by means of magnetization M and specific heat C-p measurements, evidencing the formation of the long-range antiferromagnetic order at T-N = 2.4 K in the former compound and paramagnetic behavior down to 2 K in the latter compound. Large magnetocaloric effect allows considering GdFeTeO6 for the magnetic refrigeration at liquid hydrogen stage. Density functional theory calculations produce estimations of leading Gd-Gd, Gd-Fe and Fe-Fe interactions suggesting unique chiral 120 & DEG; magnetic structure of Fe3+ (S = 5/2) moments and Gd3+ (J = 7/2) moments rotating in opposite directions (clockwise/anticlockwise) within weakly coupled layers of the rosiaite type crystal structure.
palavras-chave
PBSB2O6; CO
categoria
Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter
autores
Zvereva, E; Vasilchikova, T; Evstigneeva, M; Tyureva, A; Nalbandyan, V; Goncalves, J; Barone, P; Stroppa, A; Vasiliev, A
nossos autores
João Nuno Santos Gonçalves
Investigador Júnioragradecimentos
This work has been supported by the grant 18-03-00714 from the Russian Foundation for Basic Research (for V.N., E.Z., and M.E.) and Grant-in-Aid 00-15 from the International Centre for Diffraction Data (for V.N. and M.E.); A.V. acknowledges the support of experimental study by Megagrant Program of the Government of Russian Federation through the project 075152021-604. A.S. and J.G. thanks HPC-Europa3 for funding.