T00_exprs

T00_exprs = [cos(\phi_i - \phi_j)*cos(\phi_k - \phi_l)/3, sqrt(3)*sin(\phi_i - \phi_j)*sin(\phi_k - \phi_l)/6, sqrt(5)*(cos(\phi_i - \phi_j - \phi_k + \phi_l) + cos(\phi_i - \phi_j + \phi_k - \phi_l) + 6*cos(\phi_i + \phi_j - \phi_k - \phi_l))/60]

Expressions for isotropic four-fold polarization tensor components (dummy angles)