Divalent manganese in A-position of perovskite cell: X-ray absorption finite structure study of La(0.6)Sr(0.4-x)MnTi(x)O(3) manganites

Local structure and magnetic properties of Ti doped A-site deficient La(0.6)Sr(0.4-x)MnTi(x)O(3+delta) manganites (0.15 >= x >= 0) have been studied. The compositions belong to rhombohedral R (3) over barc phase. Segregation of (La(0.6)Sr(0.4-x)Mn(y))(Mn(1-y-z)Ti(x))O(3+delta) phase and fallout of (z/3)Mn(3)O(4) oxide was observed with x increase. Some amount (y) of Mn, being in divalent valence state, occupies the A (=La,Sr)-position of perovskite cell. Samples with x=0 and 0.05 are ferromagnetic with Curie temperature T(C)=350 and 172 K, respectively. Samples with x=0.1 and 0.15 are in spin(cluster)-glass states at low temperatures. (c) 2008 American Institute of Physics.
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