magnopy.SpinHamiltonian.p41#

property

property SpinHamiltonian.p41: list#

Parameters of (four spins & one site) term of the Hamiltonian.

\[\boldsymbol{J}_{4,1}(\boldsymbol{r}_{\alpha})\]

of the term

\[C_{4,1} \sum_{\mu, \alpha, i, j, u, v} J^{ijuv}_{4,1}(\boldsymbol{r}_{\alpha}) S_{\mu,\alpha}^i S_{\mu,\alpha}^j S_{\mu,\alpha}^u S_{\mu,\alpha}^v\]
Returns:
parameterslist

List of parameters. The list has a form of

[[alpha, J], ...]

0 <= len(parameters) <= len(spinham.atoms.names).

where alpha is an index of the atom to which the parameter is assigned and J is a (3, 3, 3, 3) numpy.ndarray. The parameters are sorted by the index of an atom alpha in the ascending order.

See also

add_41
remove_41