:term:`MIXED <MIXED (DETCI)>`
"""""""""""""""""""""""""""""

      Do allow "mixed" RAS II/RAS III excitations into the CI space? If FALSE, then if there are any electrons in RAS III, then the number of holes in RAS I cannot exceed the given excitation level :term:`EX_LEVEL <EX_LEVEL (DETCI)>`  

      * **Type**: :ref:`boolean <op_c_boolean>`
      * **Default**: true