# register_thermoml_property

`openff.evaluator.datasets.thermoml.``register_thermoml_property`(thermoml_string, supported_phases, property_class=None, conversion_function=None)

  A function used to map a property from the ThermoML archive to an internal PhysicalProperty object of the correct type.

  This function takes either a specific class (e.g. Density) which maps directly to the specified thermoml_string, or a a function which maps a ThermoMLProperty into a PhysicalProperty allowing fuller control.

  Parameters

    - thermoml_string (str) – The ThermoML string identifier (ePropName) for this property.

    - supported_phases (PropertyPhase:) – An enum which encodes all of the phases for which this property supports being estimated in.

    - property_class (type of PhysicalProperty, optional) – The class associated with this physical property. This argument is mutually exclusive with the conversion_function argument.

    - conversion_function (function) – A function which maps a ThermoMLProperty into a PhysicalProperty. This argument is mutually exclusive with the property_class argument.