Function sequant::open_shell_P_op_vector

• Defined in File spin.cpp

Function Documentation

std::vector<ExprPtr> sequant::open_shell_P_op_vector(const Tensor &A)

Generate a vector of permutation operators for partial expansion of antisymmstrizer.

The antisymmetrizer need not be fully expanded to spin-trace for open-shell case. By expanding only the unlike spin terms, the antisymmetrizer is pereserved for same-spin particle indices.

Warning

This function assumes the antisymmetrizer (A) has a canonical form

Parameters:

A – Antisymmetrizer tensor produced in Coupled Cluster

Returns:

a vector of expression pointers containing permutation operators as a sum