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S. Khmelevskyi, P. Mohn:
"Relationship between magnetic and structural properties of Ni thin films on GaAs(100) and bulk bcc Ni: First-principles calculations";
Physical Review B, 75 (2007), 0124111 - 0124114.

Recent experimental investigation of electronic and magnetic properties of thin films of bcc Ni grown on
GaAs 001 substrate allowed to extrapolate towards the magnetic properties of normally unstable bulk bcc Ni
metal. Using first principles calculations, we find that due to the lattice mismatch Ni films on GaAs 001 are
under tension and the resulting interlayer relaxation is at about 2.5%. The comparison of the calculated
magnetic properties, including the effective interatomic Heisenberg exchange constants derived within the
Oguchi-Lichtenstein formalism, for distorted and pure bcc phases of Ni allow to draw a conclusion about the
relevance of the experimentally extrapolated properties of pure bcc Ni. We show that a lattice distortion does
not alter the values of the magnetic moments significantly, but only moderately influences the effective magnetic
exchange interactions as compared to undistorted bulk. We advocate, however, that the experimentally
estimated value of the bulk cubic magnetic anisotropy should be taken with precaution, since the omitted
contribution due to shear strain may be significant. In addition we discuss the possible existence of weak
itinerant ferromagnetism in bcc Ni films prepared under compression.