The orbital ordering of the cubic KCrF _3

摘要

The electronic, magnetic and orbital structures of KCrF _3 in the cubic phase are studied by first principles method. In the cubic phase, the three Cr-F bonds distance are equal. If the Jahn-Teller distortion is the origin of the orbital polarization, the orbital ordering would disappear. However, our theoretical calculations show that the orbital ordering exists even without the JahnTeller distortion. By studying how the orbital polarization changes with the electron correlation and the JahnTeller distortion, we found that the origin of the orbital polarization should be the electron correlation and the Jahn-Teller distortion can reinforced such polarization.