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LSDalton
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.. py:class:: LSDalton

This interface supports energy and gradient evaluations with the 
`LSDalton <http://www.daltonprogram.org/>`_ electronic structure package 
(version 2020 or later)

For example, an LSDalton :ref:`Theory <theories>` object can be specified as follows::

  my_frag = Fragment(...)

  my_theory = LSDalton(frag=my_frag,
                       method='hf',
                       basis='3-21g',
                       ...)

which would then be called as ``theory=my_theory`` in subsequent tasks.


General options
===============

.. py:attribute:: auxbasis
   :noindex:

   (default: ``''``) Auxillary basis set name

.. py:attribute:: harmonic
   :noindex:

   Allowed values:

   * ``True``: (default) Use spherical harmonic basis functions (as opposed to Cartesians)

   * ``False``: Not to use spherical harmonic basis functions

.. py:attribute:: scalapack
  
   Allowed values:

   ``False``: (default) Not to use ScaLAPACK

   ``True``: Use the ScaLAPACK linear algebra library for parallel diagonalisation. LSDalton must be compiled with ScaLAPACK enabled


SCF options
===========

.. py:attribute:: convdyn

   Allowed values:

   * ``'standard'``: (default) Standard SCF convergence criterion

   * ``'tight'``: Tight SCF convergence criterion

   * ``'sloppy'``: Sloppy SCF convergence criterion