nosi
======

This option defines the implementation details of nonothorgonal state interaction calculations.

.. contents::
   :local:

.. option:: dets_type

   .. list-table::
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      :widths: 5 20
   
      * - Value
        - ``mwfn`` for MWFN file type 
      * - Default
        - ``mwfn``

.. * - ``blw`` for GAMESS BLW file type 

   Define the file type of determinants.

.. option:: zero_threshold

   .. list-table::
      :stub-columns: 1
      :widths: 5 20
   
      * - Value
        - A real number 
      * - Default
        - ``1.E-6``

   When the overlap of two orbitals is smaller than this value, they will be treated as zero
   
   .. WARNING::
      Do not set a too large value (like ``1.E-4``). It may leads to wrong results.

.. option:: offdiag_correlation

   .. list-table::
      :stub-columns: 1
      :widths: 5 20
   
      * - Value
        - ``overlap_weighted`` Will use overlap weighted method
      * -
        - ``energy_weighted`` Will use energy weighted method
      * - Default
        - ``overlap_weighted``
    
   
   Define the off-diagonal correlation method. There are two options:

.. option:: schwarz

   .. list-table::
      :stub-columns: 1
      :widths: 5 20
   
      * - Value
        - A real number
      * - Default
        - ``1.E-10``
       
   Define the Schwarz screening tolerance. All two-electron integral contributions below this tolerance will be discarded to speed up calculations. A positive real number is needed. 

   .. WARNING::
     Do **not** set a too large value (like ``1.E-5``). It may leads to wrong results.