  Using the first-principles density-functional theory plan-wave
pseudopotential method, we investigate the structure and magnetism in 25% Mn
substitutive and interstitial doped monoclinic, tetragonal and cubic ZrO2
systematically. Our studies show that the introduction of Mn impurities into
ZrO2 not only stabilizes the high temperature phase, but also endows ZrO2 with
magnetism. Based on the simple crystal field theory (CFT), we discuss the
origination of magnetism in Mn doped ZrO2. Moreover, we discuss the effect of
electron donor on magnetic semiconductors, and the possibility as electronic
structure modulator.
