Pressure dependence of magnetic properties of CrO2 from theory

Samir F. Matar (1) , Gérard Demazeau (1)

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux

From self-consistent electronic structure calculations bulkmodulus of CrO2 (270 GPa) is within agreement of experimental value 280 ± 20 GPa. At different simulated isotropic compressions the system remains half metallic for 1 < P < 60 GPa then becomes metallic with lowered magnetization for 60 < P < 120 GPa. This is accompanied by decreasing energy difference between the ferromagnetic ground state and an antiferromagnetic configuration so that both are accessible at high pressures. Spin fluctuation theory analysis points to critical pressure for magnetic order disappearance PC = 150 GPa and dTC/dP = −0.027 K GPa−1. This positions CrO2 between soft (Invar) and very hard (fcc–Ni) magnetic systems pointing to its magnetic hardness.

Mots clés: High pressure; Magnetic properites; CrO2; Chrome oxide; Electronic structure calculation

Domaines: Matériaux

Samir F. Matar, Gérard Demazeau. Pressure dependence of magnetic properties of CrO2 from theory. Chemical Physics Letters, 2005, 407 (4-6), pp.516-521. ⟨10.1016/j.cplett.2005.03.148⟩. ⟨hal-00081515⟩