pytzer

pytzer is a Python 3.6+ implementation of the Pitzer model for chemical activities in aqueous solutions (Pitzer, 1991).

Installation

If using conda, first create and activate a new environment with Python 3.6 and numpy 1.15. Then:

pip install pytzer

Other versions are probably fine, but untested. We are using Python 3.6 rather than 3.7 to enable planned integration with MATLAB.

See the quick-start guide for more detailed instructions and examples.

Development status

pytzer is in beta. Tests of the accuracy of its coefficients and equations are underway, so results may change. API may change and functions may be added or removed. Use at your own peril!

Modules

Module	Purpose
.io	Import and export data
.cflibs	Define combinations of model coefficients to use
.model	Implement the Pitzer model
.coeffs	Define functions to evaluate model coefficients
.tables	Store tables of coefficient values
.jfuncs	Define unsymmetrical mixing functions
.props	Define universal ionic properties
.constants	Define physical constants
.meta	Define package metadata

Acknowledgements

pytzer is maintained by Dr Matthew P. Humphreys at the Centre for Ocean and Atmospheric Sciences, School of Environmental Sciences, University of East Anglia, Norwich, UK.

Its ongoing development is funded by the Natural Environment Research Council (NERC, UK) through NSFGEO-NERC: A Thermodynamic Chemical Speciation Model for the Oceans, Seas, and Estuaries (NE/P012361/1).

License

The entirety of pytzer is licensed under the GNU General Public License version 3 (GPLv3).

References

Pitzer, K. S. (1991). “Ion Interaction Approach: Theory and Data Correlation,” in Activity Coefficients in Electrolyte Solutions, 2nd Edition, ed. K. S. Pitzer (CRC Press, Florida, USA), 75–153.