:orphan:
 

.. index:: **WAVE FUNCTION
.. _**WAVE FUNCTION:

=================
\*\*WAVE FUNCTION
=================


**Get the wave function**
=========================

This section allows the specification of which wave function module(s)
to activate. By default no modules are activated. To activate any of
these modules you must also specify :ref:`DIRAC_.WAVE FUNCTION`
under :ref:`**DIRAC`,
otherwise this input is not read.

Note that the order below specifies the order in which the different
modules are called if you ask for more than one.


.. index:: .SCF
.. _WAVE_FUNCTION_.SCF:

.SCF
----

Activates the Hartree-Fock/Kohn-Sham module.

Specification of the SCF module can be given in the :ref:`*SCF` subsection.

If :ref:`HAMILTONIAN_.DFT` has been specified
under :ref:`**HAMILTONIAN`, then a
Kohn-Sham calculation will be performed, otherwise a Hartree-Fock
calculation will be performed.


.. index:: .RESOLVE
.. _WAVE_FUNCTION_.RESOLVE:

.RESOLVE
--------

Resolve open-shell states: do a small CI calculation to get the
individual energies of the states present in an
average-of-configurations open-shell Hartree-Fock calculation (see
:ref:`*RESOLVE`).

.. index:: .COSCI
.. _WAVE_FUNCTION_.COSCI:

.COSCI
------

Activates advanced COSCI method, see :ref:`*COSCI`.


.. index:: .MP2
.. _WAVE_FUNCTION_.MP2:

.MP2
----

Activates :ref:`*MP2CAL`.


.. index:: .MVO
.. _WAVE_FUNCTION_.MVO:

.MVO
----

Calculate modified virtual orbitals (see :ref:`*MVOCAL`).
Default after open-shell SCF is modified virtual orbitals based on the closed-shell molecular orbitals.
There is no default for closed-shell SCF.

.. index:: .MP2 NO
.. _WAVE_FUNCTION_.MP2 NO:

.MP2 NO
-------

Activates the :ref:`*MP2 NO` module to calculate MP2 natural orbitals.

.. index:: .RELCCSD
.. _WAVE_FUNCTION_.RELCCSD:

.RELCCSD
--------

Activates the  :ref:`**RELCC`
(and the :ref:`**MOLTRA`
module to get 4-index
transformed integrals).

By default, molecular orbitals with orbital energy between -10 and +20
hartree (a.u.) are included, this can be modified in the
:ref:`**MOLTRA` section.


.. index:: .RELADC
.. _WAVE_FUNCTION_.RELADC:

.RELADC
-------

Activates the :ref:`RELADC` and
calculates the single and double ionization spectra by the (A)lgebraic (D)iagrammatic
(C)onstruction ADC. Also activates the :ref:`**MOLTRA`
module to get 4-index
transformed integrals.


.. index:: .POLPRP
.. _WAVE_FUNCTION_.POLPRP:

.POLPRP
-------

Activates the :ref:`**POLPRP` module for
calculation of the excitation spectrum by the strict or extended second order
(A)lgebraic (D)iagrammatic (C)onstruction ADC. Also activates the :ref:`**MOLTRA`
module to get 4-index transformed integrals.


.. index:: .DIRRCI
.. _WAVE_FUNCTION_.DIRRCI:

.DIRRCI
-------

Activates the MOLFDIR CI module (and also the
:ref:`**MOLTRA`  module to get 4-index transformed integrals).

Specification of input for the MOLFDIR CI module is given in
the :ref:`DIRRCI`  and :ref:`GOSCIP` sections.

By default, molecular orbitals with orbital energy between -10 and +20
hartree (a.u.) are included, this can be modified in the
:ref:`**MOLTRA`  section.


.. index:: .LUCITA
.. _WAVE_FUNCTION_.LUCITA:

.LUCITA
-------

Activates the :ref:`*LUCITA` (and
the :ref:`**MOLTRA` module to get 4-index
transformed integrals).

By default, molecular orbitals with orbital energy between -10 and +20
hartree (a.u.) are included, this can be modified in the
:ref:`**MOLTRA` section.


.. index:: .EXACC
.. _WAVE_FUNCTION_.EXACC:

.EXACC
------

Activates the  :ref:`**EXACC` module, the new coupled cluster implementation
based on the ExaTensor library.


**Pre-SCF orbital manipulations**
=================================

.. index:: .REORDER MO
.. _WAVE_FUNCTION_.REORDER MO:

.REORDER MO
-----------

Interchange initial molecular orbitals prior to the SCF-calculation. The
start orbitals from DFCOEF are read and reordered.

For each fermion irrep give the new order of orbitals.

*Example:*

::

    .REORDER MO'S
    1..8,10,9


.. index:: .ORBROT
.. _WAVE_FUNCTION_.ORBROT:

.ORBROT
-------

Jacobi rotations between pairs of orbitals.

On the line following the keyword, give first the rotation angle, then
on the following line(s) for each fermion irrep, give an :ref:`orbital_strings`
of orbitals to
rotate.


**Post-SCF orbital manipulations**
==================================

.. index:: .POST SCF REORDER MO
.. _WAVE_FUNCTION_.POST SCF REORDER MO:

.POST SCF REORDER MO
--------------------

Interchange converged molecular orbitals. The orbitals from DFCOEF are
read and reordered just before exiting the SCF subroutine.

For each fermion irrep give the new order of orbitals.

*Example:*

::

    .POST DHF REORDER MO'S
    1..8,10,9


.. index:: .PHCOEF
.. _WAVE_FUNCTION_.PHCOEF:

.PHCOEF
-------

Phase adjustment of coefficients DFCOEF: make the largest element of a
given orbital real and positive.


.. index:: .KRCI
.. _WAVE_FUNCTION_.KRCI:

.KRCI
-----

Activates the :ref:`*KRCI` module
for the calculation of ground and excited states at the relativistic CI level.

.. index:: .KRMCSCF
.. _WAVE_FUNCTION_.KRMCSCF:

.KRMCSCF
--------

Activates the :ref:`*KRMCSCF`
module for the optimization of ground and excited states (in other than the ground state symmetry) 
at the relativistic MCSCF level.

.. index:: .LAPLCE
.. _WAVE_FUNCTION_.LAPLCE:

.LAPLCE
-------

Activates the :ref:`*LAPLCE`
module to compute weights for Laplace transformation of orbital
energy denominators with the algorithm of Helmich-Paris.
No subsequent calculations, only output of the Laplace points and weights.