SZ — Specify value of S_{z}.

SZ=`n`

For a set of spin adapted microstates which is degenerate in both spin multiplicity and
energy, only a single member of the set is included in the expansion of the CI eigenstates. By
default, the spin adapted microstate with the smallest non-negative S_{z}
eigenvalue is chosen, i.e., S_{z} = 0 for systems with an even number of
electrons and S_{z} = 1/2 for systems with an odd number of electrons.
This behavior can be overridden using this keyword, where the value of
S_{z} used will be shifted by n from the default value. For example, for
even-electron systems with SZ=1 specified, all of the spin adapted microstates used will have
S_{z} = 1, i.e. two more alpha spin orbitals occupied than beta spin
orbitals. For odd-electron systems with SZ=1 specified, the spin adapted microstates used will
have S_{z} = 3/2, i.e., three more alpha spin orbitals occupied than beta
SOs. Of course, the value of S_{z} desired should not exceed the total
spin corresponding to the specified spin multiplicity keyword. For example, specifying
DOUBLET together with SZ=1 will not work
because a doublet eigenstate cannot be expanded in terms of quartet microstates. For the same
reason, if QUARTET is specified along
with SZ=1 and CISTATE=n with
n > 1, no doublet states will be generated.

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