Relationship between coupling constants in Heisenberg exchange Hamiltonian and Ising model

- Coupling constants in Heisenberg exchange Hamiltonian and Ising model.
- J(Hei) = J(Ising)/N where N is the number of equivalent magnetic sites per cell.
- Three systems with N > 1 are discussed as examples.
- MnSb alloy, meta-xylylene polyradical, silicon substituted polyradical.