Discrepancy: majorMicrospecies & microspecies distribution

User 254af5a71f

16-10-2014 21:21:00


I have been using JCChemicalTerms(molecule,majorMicrospecies("7.2")) to calculate the formula for many compounds at pH 7.2. However, upon doing a pKa calculation in Marvin, the microspecies predicted to dominate at pH 7.2 is often different from what JCChemicalTerms gave in the previously mentioned method.

So I'm wondering: which method should I trust??

This actually happens for many compounds, and I attached the sdf file for two of them. Both compounds are documented in PubChem.

Thank you.

ChemAxon d51151248d

22-10-2014 13:49:44

Dear Cleo, 

the problematic issue does not exist in the current version of the ChemAxon softwares. Can you tell us which version you use? We also recommend to update your current version.

Best regards, 


User 254af5a71f

23-10-2014 21:19:09

The version I'm using is 14.9.2900.1033. Thanks!