Hyperfine interactions, charge compensation mechanisms, and the distribution of tin dopant cations in rare-earths orthochromites RCrO3 (R = Sm, Eu, Gd, Ho)

Pavel B. Fabritchnyi (1) , Mikhail I. Afanasov (1) , Evgueny Mezhuev (1) , R. A. Astashkin (1) , Alain Wattiaux (2) , Sylvie Bourdineaud-Bordère (2) , Christine Labrugère (2) , Claude Delmas (2)

1 Department of Chemistry, Lomonosov Moscow State University
2 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux

The reduction in the squared cosine of angle θ of the Cr-O-Cr bond in the Sm-Ho series in sam ples containing Sn4+ ions in the Cr3+ position in the crystallite bulk is accompanied by a linear increase in hyperfine field HT→0 K at 119Sn nuclei. Upon annealing in H2, tin attains oxidation state +2 occupying the Cr3+ and R3+ positions on the surfaces of particles. Mössbauer measurements in situ at 100 K do not reveal the spin polarization of Sn2+, but this polarization does manifest itself for part of the daughter Sn4+ ions formed when samples come into contact with air.

Mots clés: Rare earths; Mössbauer spectroscopy; Tin; Cations

Domaines: Matériaux

Pavel B. Fabritchnyi, Mikhail I. Afanasov, Evgueny Mezhuev, R. A. Astashkin, Alain Wattiaux, et al.. Hyperfine interactions, charge compensation mechanisms, and the distribution of tin dopant cations in rare-earths orthochromites RCrO3 (R = Sm, Eu, Gd, Ho). Bulletin of the Russian Academy of Sciences - Physics, 2013, 77 (6), pp.819-826. ⟨10.3103/S1062873813060117⟩. ⟨hal-00837864⟩