Hi @Sam_Blau
Thank you for your reply. I have followed the procedure you outlined and have ensured that the molecular structure does not have imaginary frequencies. But, I still cannot reproduce the result on Material Project. For example, I try to test ethylene carbonate (EC) for IE calculation. The IE value I have calculated by Gaussian is about 8.417 eV (The IE value on Material Project is 7.044 eV). I do not think that 1.37 eV is a slight difference. Could you help me figure out the large discrepancy? I have put my input files and output files for my calculation in this link. In addition, in this discussion, you mention that molecules in Explore Molecules have already converted IE value to voltage vs. Li/Li+, so perhaps my calculation is consistent with your result, if I subtract 1.4 eV from our result.
I also found that there is still a problem some molecules’ IP / EA and redox potentials on Lithium are set to the same values, such as EC.
Best,
Hsiu