resumo
We present a study of magnetic and structural properties of La1-xGdxCoO3 compounds with x = 0, 0.2, 0.5 and 1. The Gd term in magnetic susceptibility obeys the Curie-Weiss law with antiferromagnetic interaction between the magnetic moments of Gd3+ ions. The value of the paramagnetic Curie temperature.. is proportional to Gd content and for GdCoO3 it reaches Theta similar or equal to -5.5 K. The Co contribution, chi(Co)(T), derived by subtracting the Gd term from the total susceptibility, shows a non-monotonous behavior which is originated by the temperature induced transition of Co3+ ions from the ground low spin state to a higher spin state separated by an energy Delta The revealed strong increase in.. with increasing Gd content is presumably due to the manifestation of a chemical pressure upon replacing La with Gd having a smaller ionic size.
palavras-chave
SPIN-STATE TRANSITION; COBALT OXIDES; PRESSURE; LACOO3
categoria
Physics, Condensed Matter
autores
Panfilov, AS; Grechnev, GE; Lyogenkaya, AA; Pashchenko, VA; Vasylechko, LO; Hreb, VM; Kovalevsky, AV
nossos autores
Andrei Kavaleuski
Investigador principalProjectos
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
agradecimentos
A.V.K. acknowledges the support of the project CICECO-Aveiro Institute of Materials, Portugal (ref. UIDB/50011/2020 and UIDP/50011/2020) and the project POCI-01-0145-FEDER-031875, financed by COMPETE 2020 Program and National Funds, Portugal through the FCT/MEC and when applicable co-financed by FEDER under the PT2020 Partnership Agreement. Some authors (L.O.V., V.M.H.) acknowledge partial support of the Ukrainian Ministry of Education and Sciences under project N 0118U000264 Ferryt''.