.. _ref-eos:

Equations of State for Minerals
-------------------------------

To calculate the thermodynamic and thermoelastic properties of a material
at a given pressure (:math:`P`) and temperature (:math:`T`), a formulation
is required that describes how the Gibbs energy (or any of the other three
thermodynamic potentials) varies with pressure and temperature. These
formulations are known as equations of state (EoS). In BurnMan, each mineral
is associated with an EoS, and the mineral knows which EoS to use via a key
called "equation\_of\_state" in its parameter dictionary
(this dictionary is passed as an argument when creating the mineral). The
value of this key can either be the EoS class itself, an instance of the
EoS class, or a string that identifies the EoS. The valid string keys
are listed below.

Currently the following EoSs are supported in BurnMan:

.. contents::
   :local:
   :class: this-will-duplicate-information-and-it-is-still-useful-here
   :depth: 3

These EoSes are described in more detail below.

Isothermal Equations of State
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Isothermal equations of state describe the relationship between pressure
and volume at a constant temperature. BurnMan includes several isothermal
equations of state.

.. include:: autogenerated/isothermal_eos.rst

Thermal Equations of State
~~~~~~~~~~~~~~~~~~~~~~~~~~

Thermal equations of state account for the effects of temperature on
thermoelastic properties. BurnMan includes several thermal equations of state.

.. include:: autogenerated/thermal_eos.rst