Structural, magnetic and transport properties in the manganites La0.7Sr0.3-xTexMnO3 (0 ≤ x ≤ 0.15)

The effect of Te-doping at La-site on structural, magnetic and transport properties in the manganites La(0.7)Sr(0.3-x)TexMnO(3) (0 <= r <= 0.15) has been investigated. All samples show a rhombohedral structure with the space group R3C. It shows that the Mn-O-Mn bond angle decreases and the Mn-O bond length increases with the increase of Te content. The Curie temperature T-C decreases with increasing Te-doping level, in contrast, the magnetization magnitude of Te-doping samples at low temperatures increase with increasing x as x <= 0.05 and then decrease with further increasing x to 0.15. The results are discussed in terms of the combined effects of the opening of the new double exchange (DE) channel between Mn2+-O-Mn3- due to the introduction of Mn2+ ions because of the substitution of Te4+ or Sr2+ and the reduction of the transfer integral b due to the decrease of the Mn-O-Mn bond angle. (c) 2005 Elsevier Ltd. All rights reserved.