****
MNDO
****

.. py:class:: MNDO

This interface supports energy and gradient evaluations with the
MNDO semi-empirical electronic structure package developed by the 
group of Walter Thiel at MPI Muelheim.

As a QM interface, the options described in :doc:`qm` are available,
as well as the MNDO specific options outlined below.

.. note:: MNDO is a semi-empirical code, so the interface will ignore
 some QM keyword options that are not applicable e.g. ``basis``, ``ecp``, ``functional``.

An MNDO :ref:`Theory <theories>` object can be specified as follows::

  my_frag = Fragment(...)

  my_theory = MNDO(frag=my_frag,
                   method='am1',
                   ...)

which would then be called as ``theory=my_theory`` in subsequent tasks (see :ref:`Tasks <tasks>`).

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

.. py:attribute:: method

   (default: ``mndo``) Semi-empirical method to use, e.g. ``mndo``, ``am1``, ``pm3``, ``om2``.


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

.. py:attribute:: accuracy

   (default: ``medium``) SCF accuracy setting. ``high`` sets SCF convergence to 10^-8 eV. ``veryhigh`` sets SCF convergence to 10^-10 eV.