Magnetism: Magnetic ions in insulators, their interactions, resonances, and optical properties

anisotropy energy antiferromagnetic antiferromagnetic resonance antiparallel assumed atoms axes axis calculation Co2+ coefficients components constant covalency crystal field crystal field theory crystalline field cubic Curie temperature direction discussed effect electrons energy levels equations exchange integral exchange interaction excited experimental expression external field Fe2+ Fe3+ ferrites field theory given by Eq Hartree-Fock induced anisotropy iron garnet K₁ lattice ligand field ligand field theory linear M₁ magnetic dipolar interaction magnetic field magnetic ions magnetic moment magnetostriction matrix elements molecular field approximation nearest-neighbor Néel Néel temperature neighbors Ni2+ NiF₂ observed obtained optical orientation orthogonal P. W. Anderson pair parallel paramagnetic parameters phenomenological Phys plane problem pseudodipolar result S₁ S₂ Section spin arrangement spin Hamiltonian spin wave spin-orbit coupling splitting sublattice magnetizations superexchange susceptibility symmetry temperature dependence theoretical torque transition trigonal values vector Vleck wave function weak ferromagnetism ytterbium zero