Local structure and polaron formation in Lal_xCaxMnO3
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چکیده
The local structure of La 1 .~Ca~MnO 3 is determined from pair-distribution function (PDF) analysis of pulsed neutron diffraction. We have compared the effect on the local structure of crossing the metal-insulator transition as a function of temperature and composition. Crossing the metal insulator boundary at low temperature by varying the composition yields similar distortions to those seen in the temperature dependence indicating the presence of polarons in the insulating phase which disappear in the metallic phase. ~', 1998 Published by Elsevier Science B.V. All rights reserved.
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