oqp.library.frequency
=====================

.. py:module:: oqp.library.frequency

.. autoapi-nested-parse::

   .. code-block:: text

      OQP frequency analysis



Attributes
----------

.. autoapisummary::

   oqp.library.frequency.IR_INTENSITY_CONVERSION_KM_MOL


Functions
---------

.. autoapisummary::

   oqp.library.frequency.infrared_intensities
   oqp.library.frequency.raman_activities
   oqp.library.frequency.normal_mode
   oqp.library.frequency.thermal_analysis


Module Contents
---------------

.. py:data:: IR_INTENSITY_CONVERSION_KM_MOL
   :value: 42.255


.. py:function:: infrared_intensities(dipole_derivatives, modes)

   .. code-block:: text

      Project Cartesian dipole derivatives onto normal modes.

      :param dipole_derivatives: Array with shape ``(3, 3N)`` containing d(mu_x,mu_y,mu_z)/dR in
                                 atomic units.
      :param modes: Normal modes with shape ``(nmode, 3N)`` as returned by ``normal_mode``.

      :returns: IR intensities in km/mol and the mode-projected dipole derivatives.
      :rtype: intensities, mode_dipoles


.. py:function:: raman_activities(polarizability_derivatives, modes)

   .. code-block:: text

      Project Cartesian polarizability derivatives and compute Raman activities.

      ``polarizability_derivatives`` has shape ``(3, 3, 3N)`` in atomic units.
      The returned activities follow the standard non-resonant expression
      ``45 * alpha_bar'^2 + 7 * gamma'^2`` for each normal mode.


.. py:function:: normal_mode(coord, mass, hessian)

.. py:function:: thermal_analysis(energy, atoms, mass, freqs, inertia, temperature=298.15, linear=False, mult=0, freq_scale_factor=1, freq_cutoff=100)