Exchange-Correlation (XC) Functionals
=====================================

Local Density Approximation (LDA) XC Functionals
------------------------------------------------

Perdew-Zunger (PZ) Functional
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. autofunction:: functionals.PerdewZunger

Perdew-Wang (PW) Functional
^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. autofunction:: functionals.PerdewWang

Chachiyo Functional
^^^^^^^^^^^^^^^^^^^

.. autofunction:: functionals.Chachiyo


Generelized Gradient Approximation (GGA) XC Functionals
-------------------------------------------------------

Perdew-Burke-Ernzerhof (PBE) Functional
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. autofunction:: functionals.PerdewBurkeErnzerhof