Cationic Disorder in Co₂AlBO₅: Effects on Magnetic and Electrical Properties

Abstract

Single crystals of Co 2 AlBO 5 were synthesized using flux. The structural, magnetic, and electrical properties have been studied, with emphasis on cationic disorder effects. The Al 3+ and Co 2+ ions share four symmetry inequivalent sites. Large amplitudes of the displacement parameters for the M2 and M4 metal sites and the O4 oxygen site were found. The compound exhibits two magnetic transitions at T 1 = 41 K and T 2 = 20 K and shows a high crystallographic anisotropy. The random cationic distribution induces magnetic softness and an increase in electrical resistivity. The sources of the cationic disorder and the approach for controlling it are discussed.