This tool allows to calculate Hammett sigma constants characterizing electron donating and withdrawing power of substituents. These properties are obtained using quantum chemical calculations. Details about the methodology are available in
this open access article in Chemistry-Methods.
To start the calculations, draw your substituent and mark its connection with the rest of the molecule by using the R atom. For example to calculate properties of oxazolyl, provide the following input:
Together with the σ-meta and σ-para constants also the Hanch π hydrophobicity substituent parameter is provided, calculated using fragment contributions.
The results are provided with hope to be useful, but, of course, without any warranty. By using this tool you also accept the use of cookies, that are used to store the drawn structures in the
JSME editor (so you do not need to draw the molecules every time).
If you have any suggestions or comments, do not hesitate to contact me.
Acknowledgements:
I want to thank Prof. Grimme for releasing his excellent xtb program to the public and to Molinspiration Cheminformatics for allowing me to use their Galaxy SMILES to 3D converter as well as the mib package to calculate substituent hydrophobicity.