Zeeman interaction

Zeeman interaction involves two entities. Therefore, it can be expressed as a \(\mathcal{H}_2\) term.

\[\mathcal{H}_2 = C_2 \sum_{\mu_1, \mu_2; \alpha_1, \alpha_2; i_1, i_2} V_{\mu_1, \mu_2; \alpha_1, \alpha_2}^{i_1, i_2} X_{\mu_1; \alpha_1}^{i_1} X_{\mu_2; \alpha_2}^{i_2}\]

The summary of the mapping for each code is given in the table below.

Code

Magpie, SpinW

McPhase (v1)

McPhase (v2)

Spirit

Sunny

\(\mathcal{H}\)

\[\mathcal{H} = \mu_B \mathbf{H} \sum_{i} g_i \mathbf{S}_i\]
\[\hat{\mathcal{H}}_{Z-J} = - \sum_{n, \alpha=1,2,3} g_n \mu_B \hat{J}^{n}_{\alpha} H_{\alpha}\]
\[\hat{\mathcal{H}}_{Z-LS} = - \sum_{n, \alpha=1,2,3} \mu_B \Bigl( 2 \hat{S}^n_{\alpha} + \hat{L}^n_{\alpha} \Bigr) H_{\alpha}\]
\[\mathcal{H}_{\rm Zeeman} = -\sum_i \mu_i \vec{B}\cdot \vec{n}_i\]
\[\mathcal{H} = \mu_B \mathbf{B} \sum_{i} g_i \mathbf{S}_i\]

Renaming of indices

\(i \rightarrow (\mu_2, \alpha_2)\), \(i_1, i_2 = x, y, z\)

\(n \rightarrow (\mu_2, \alpha_2)\), \(\alpha \rightarrow i_1\) and \(\alpha \rightarrow i_2\)

\(n \rightarrow (\mu_2, \alpha_2)\), \(\alpha \rightarrow i_1\) and \(\alpha \rightarrow i_2\)

\(i \rightarrow (\mu_2, \alpha_2)\), \(i_1, i_2 = x, y, z\)

\(i \rightarrow (\mu_2, \alpha_2)\), \(i_1, i_2 = x, y, z\)

\(C_2\)

1

-1

-1

-1

1

\(V_{\mu_1, \mu_2; \alpha_1, \alpha_2}^{i_1, i_2}\)

\(\mu_B g_{\mu_2, \alpha_2} \delta_{i_1, i_2} \delta_{\mu_1, \mu_2} \delta_{\alpha_1, \alpha_2}\)

\(g_{\mu_2, \alpha_2} \mu_B \delta_{i_1, i_2} \delta_{\mu_1, \mu_2} \delta_{\alpha_1, \alpha_2}\)

\(\mu_B \delta_{i_1, i_2} \delta_{\mu_1, \mu_2} \delta_{\alpha_1, \alpha_2}\)

\(\mu_{\mu_2, \alpha_2} \delta_{i_1, i_2} \delta_{\mu_1, \mu_2} \delta_{\alpha_1, \alpha_2}\)

\(\mu_B g_{\mu_2, \alpha_2} \delta_{i_1, i_2} \delta_{\mu_1, \mu_2} \delta_{\alpha_1, \alpha_2}\)

\(X_{\mu_1, \alpha_1}^{i_1}\)

\(H^{i_1}\)

\(H^{i_1}\)

\(H^{i_1}\)

\(B^{i_1}\)

\(B^{i_1}\)

\(X_{\mu_2; \alpha_2}^{i_2}\)

\(S_{\mu_2, \alpha_2}^{i_2}\)

\(\hat{J}^{\mu_2, \alpha_2}_{i_2}\)

\(2 \hat{S}^{\mu_2, \alpha_2}_{i_2} + \hat{L}^{\mu_2, \alpha_2}_{i_2}\)

\(n_{\mu_2, \alpha_2}^{i_2}\)

\(S_{\mu_2, \alpha_2}^{i_2}\)