### many imaginary freq for initial minimum

Posted:

**Tue Apr 27, 2021 8:34 pm**Hello everyone!

I hope you are all doing well in these difficult times! I am trying to calculate the ZPE for the initial minimum of an elementary step. After the dymmatrix calculation, I get 23 imaginary frequencies of which most of them are near zero. I used the dymzpbar.pl script and it resulted in a zpe of 0.634 eV. The zpe of the saddle was 2.094 eV (with one img freq). This results in a very high zpe correction to the barrier of 1.46 eV which doesn't make sense. Can someone take a look at the files attached (including optimization of the initial) and let me know where I am going wrong? I highly appreciate your time on this! Thank you!

I hope you are all doing well in these difficult times! I am trying to calculate the ZPE for the initial minimum of an elementary step. After the dymmatrix calculation, I get 23 imaginary frequencies of which most of them are near zero. I used the dymzpbar.pl script and it resulted in a zpe of 0.634 eV. The zpe of the saddle was 2.094 eV (with one img freq). This results in a very high zpe correction to the barrier of 1.46 eV which doesn't make sense. Can someone take a look at the files attached (including optimization of the initial) and let me know where I am going wrong? I highly appreciate your time on this! Thank you!