Role of spin quantization in determining the thermodynamic properties of magnetic transition metals
F. Körmann, A. Dick, T. Hickel, J. Neugebauer.
Physical Review B, 83, 165114, (2011)
We propose a combined ab initio-spin quantum Monte Carlo (QMC) approach to compute thermodynamic properties of magnetic materials by first principles. The key to the proposed approach is a mapping of the magnetic long-range system onto an effective, nearest-neighbor quantum Heisenberg model, for which the QMC approach provides a numerically exact solution. The performance of the proposed method is demonstrated for the transition metals Fe, Co, and Ni by computing magnetization shapes, specific heat capacities, and free energies. Spin-quantization effects are found to be critical, even close to T-C.
Keyword(s): iron; systems