S2_expval_exc

public interface S2_expval_exc

Evaluates $< D_i | S^2 | D_i >$

Type	Intent	Optional	Attributes		Name
integer,	intent(in)			::	nI(:)	The bra Slater determinant in nI format.
type(Excite_0_t),	intent(in)			::	exc

The matrix element. It is real even for complex NECI.

Evaluates $< D_i | S^2 | a^\dagger_A a_I D_i > = 0$

Type	Intent	Optional	Attributes		Name
integer,	intent(in)			::	nI(:)	The bra Slater determinant in nI format.
type(Excite_1_t),	intent(in)			::	exc

The matrix element is always exactly zero

Evaluates $< D_i | S^2 | a^\dagger_A a^\dagger_B a_I a_J D_i > = 0$

Type	Intent	Optional	Attributes		Name
integer,	intent(in)			::	nI(:)	The bra Slater determinant in nI format.
type(Excite_2_t),	intent(in)			::	exc

The matrix element. It is real even for complex NECI.

Evaluates $< D_i | S^2 | a^\dagger_A a^\dagger_B a^\dagger_C a_I a_J a_K D_i > = 0$

Type	Intent	Optional	Attributes		Name
integer,	intent(in)			::	nI(:)	The bra Slater determinant in nI format.
type(Excite_3_t),	intent(in)			::	exc

The matrix element is always exactly zero