The Jahn–Teller effect and electron–phonon ... (J. Phys.: Condens. Matter 13 (2001) 6195–6202)
نویسندگان
چکیده
Abstract The ultrasonic (longitudinal and transverse) velocities and the transport and magnetic properties of polycrystalline La0.25Ca0.75Mn1−xCrxO3 (x = 0, 0.03, 0.05, and 0.07) have been studied systematically. It was found that with increasing Cr content, the resistivity increases, the charge-ordering transition temperature TCO shifts to low temperature, and the magnetic moment of the system is strengthened. From the temperature dependence of the ultrasonic velocities, one can establish that the Jahn–Teller energy and phonon exchange constant decrease with increasing Cr content.
منابع مشابه
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