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 Structure Optimization (ORCA)
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This page covers geometry optimization and single point calculations using ORCA.

***********************
 Geometry Optimization
***********************

Find the minimum energy structure by adjusting atomic positions.

.. code:: bash

   chemsmart sub [OPTIONS] orca [ORCA_OPTIONS] opt [SUBCMD_OPTIONS]

Optimization Options
====================

.. list-table::
   :header-rows: 1
   :widths: 30 15 55

   -  -  Option
      -  Type
      -  Description

   -  -  ``-f, --freeze-atoms``
      -  string
      -  Atom indices to freeze (1-based indexing)

   -  -  ``-i, --invert-constraints/--no-invert-constraints``
      -  bool
      -  Invert frozen atom constraints (default: disabled)

Basic Usage
===========

Standard geometry optimization:

.. code:: bash

   chemsmart sub orca -p project -f input.xyz opt

Optimization with frozen atoms:

.. code:: bash

   chemsmart sub orca -p project -f molecule.xyz opt -f 1,2,3

Optimization with inverted constraints:

.. code:: bash

   chemsmart sub orca -p project -f molecule.xyz opt -f 1,2,3 -i

***************************
 Single Point Calculations
***************************

Compute energy and properties at a fixed geometry.

.. code:: bash

   chemsmart sub [OPTIONS] orca [ORCA_OPTIONS] sp

Basic Usage
===========

Standard single point calculation:

.. code:: bash

   chemsmart sub orca -p project -f input.xyz sp