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GAMESS-UK
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.. py:class:: GAMESS-UK
This interface supports energy and gradient evaluations with the
`GAMESS-UK `_ electronic structure package
(v8, revision 6325 or later)
A GAMESS-UK :ref:`Theory ` object can be specified as follows::
my_frag = Fragment(...)
my_theory = GAMESS_UK(frag=my_frag,
method='hf',
basis='3-21g',
...)
which would then be called as ``theory=my_theory`` in subsequent tasks (see :ref:`Tasks `).
General options
===============
.. py:attribute:: memory
:noindex:
(default: ``52000000``) Main memory request in words (8 bytes)
.. py:attribute:: harmonic
Allowed values:
* ``False``: (default) Do not use spherical harmonic basis functions (as opposed to Cartesians)
* ``True``: Use spherical harmonic basis functions (as opposed to Cartesians)
SCF options
===========
.. py:attribute:: direct
Allowed values:
* ``False``: (default) Switch off :py:attr:`direct`
* ``True``: Request direct evaluation for a given wavefunction. For open shell systems the SCF type must be specified with ``scftype=``, as the default ``scft direct`` only supports the RHF closed-shell wavefunction.
.. py:attribute:: maxcycles
(default: ``50``) Maximum number of SCF cycles permitted
.. py:attribute:: scf_threshold
(default: ``5``) SCF convergence threshold :py:attr:`10E-scf_threshold`.
.. py:attribute:: newscf
(default: ``''``) Free text input for *newscf* directives: can be either Python multi-line string (such as ``'''...'''``) or a filename (e.g., ``'my_newscf.txt'``) of plain text containing multi-line string.