triqs.operators.util.U_matrix.clebsch_gordan

triqs.operators.util.U_matrix.clebsch_gordan(jm1, jm2, jm3)[source]

Calculate the Clebsh-Gordan coefficient

\[\begin{split}\langle j_1 m_1 j_2 m_2 | j_3 m_3 \rangle = (-1)^{j_1-j_2+m_3} \sqrt{2 j_3 + 1} \begin{pmatrix} j_1 & j_2 & j_3\\ m_1 & m_2 & -m_3 \end{pmatrix}.\end{split}\]
Parameters:
  • jm1 (tuple of integers) – (j_1 m_1)

  • jm2 (tuple of integers) – (j_2 m_2)

  • jm3 (tuple of integers) – (j_3 m_3)

Returns:

cgcoeff – Clebsh-Gordan coefficient.

Return type:

scalar