Anomalous Thermal Expansion Due to Paramagnetic Impurity Ions
نویسندگان
چکیده
Paramagnetic ions will influence the thermal expansion of an insulating crystal at temperatures close the Schottky specific heat peak. When the ion exhibits a dynamic Jahn-Teller effect, tunneling between different modes . distortion can occur. The sensitivity of the level splittings to the height of the tunnelling barrier then leads to an exce R tionally .large contribution. Experimental investigation of the anomaly could thus provide useful information on t e nature of level splittings several cm1 which are at present inaccess~ble to resonance techn~ques. A numerical estimate is given for Crz+ in MgO.
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