Jump to content
Geochemist's Workbench Support Forum

Pitzer ternary parameters


Recommended Posts

In connection with another activity I had a look back in an older forum topic of mine and the following conversation by Email with Tom Meuzelar that was not held via the forum because of its very detailed content. By doing so I wondered about one of the comments of a developer that was added and that I obviously have overlooked before:


If he is using a dataset with "activity model: pitzer" in the header lines, he should be aware there are known issues with that method, as implemented in EQ3/6 some years ago. Most significantly, in order to get correct results, he needs to include by hand in the database zero values for whatever ternary parameters are not explicitly set there, but are employed in his calculation.


Are these “issues” relevant to EG3/6 only (where I am already aware of them). Otherwise, if such ternary parameters have to be set to zero also in GWB datasets, this should be emphasized somewhere in the documentation of GWB. In particular it would be interesting to know what GWB does if such parameters are not set to zero.


Kind regards,


Link to comment
Share on other sites

Hi Stefan,


The Thermo Datasets Appendix to the GWB Reference Manual has a section on Virial coefficients. From section A.1.10 (Release 8), "Any omitted entries for the polynmial are treated as zero values." So it looks like you don't have to worry about manually entering zero values for these coefficients.


Hope this helps,


Brian Farrell

Aqueous Solutions LLC

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...