We use first-principles calculations to study the effect of magnetic disorder
and electron correlations on the structural and thermodynamic properties of
CrN. We illustrate the usability of a special quasirandom structure supercell
treatment of the magnetic disorder by comparing with coherent potential
approximation calculations and with a complementary magnetic sampling method.
The need of a treatment of electron correlations effects beyond the local
density approximation is proven by a comparison of LDA+U calculations of
structural and electronic properties with experimental results. When magnetic
disorder and strong electron correlations are taken into account
simultaneously, pressure and temperature induced structural and magnetic
transitions in CrN can be understood.Comment: 23 pages, 7 figure