triqs.operators.util.U_matrix.t2g_submatrix

triqs.operators.util.U_matrix.t2g_submatrix(U, convention='triqs')[source]

Extract the t2g submatrix of the full d-manifold two- or four-index U matrix.

Parameters:
  • U (float numpy array) – Two- or four-index interaction matrix.

  • convention (string, optional) –

    The basis convention. Takes the values

    • ’triqs’: basis ordered as (“xy”,”yz”,”z^2”,”xz”,”x^2-y^2”),

    • ’vasp’: same as ‘triqs’,

    • ’wien2k’: basis ordered as (“z^2”,”x^2-y^2”,”xy”,”yz”,”xz”),

    • ’wannier90’: basis order as (“z^2”, “xz”, “yz”, “x^2-y^2”, “xy”),

    • ’qe’: same as ‘wannier90’.

Returns:

U_t2g – The t2g component of the interaction matrix.

Return type:

float numpy array