UT theoretical chemistry code forum

Hello Graeme,

Thank you so much for helping me understand this! I was able to visualize the modes with dymmodes2xyz.pl script! Have a nice day!

Regards,
Keerthan.

For convenience, here's the freq.dat file:

77.734380 cm^{-1} ... 0
89.764817 cm^{-1} ... 0
99.958151 cm^{-1} ... 0
103.766658 cm^{-1} ... 0
104.791463 cm^{-1} ... 0
124.317975 cm^{-1} ... 0
132.243987 cm^{-1} ... 0
134.403241 cm^{-1} ... 0
135.684423 cm^{-1} ... 0
138.396969 cm^{-1} ... 0 ...

Hello everyone!

I am new to the entropy calculation from vib frequencies. I have attached a completed vib freq calculation with some surface atoms(17) included and I am trying to identify the modes responsible for entropy contribution in the adsorbed state. I see a lot of literature where people ...

Hello Graeme!

Hope you are doing well.
I resolved this problem by including more atoms (top two layers) from the slab in the calculation. Now I have no imaginary modes (as expected).
Thank you for your time on this!

Regards,
Keerthan.

Hello Arindam,

Just to clarify, if we do not use LDIPOL = TRUE, we would not see a 'bump on the potential line when we plot for the WF from the LOCPOT file?

Thank you!

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 ...

Oh! That's a terrible mistake. Looks like I forgot to copy the TS to POSCAR! Thank you so much for identifying that. I will be more careful from now on.

Hello Graeme!

I am trying to extract the freq from the dynamical matrix calculation using the dymmatrix.pl script. I got an error "Illegal division by zero at /*/dymmatrix.pl at line 170". I saw on the forum that this was addressed before with a new v5.4 script. I used that script too and got a ...

Thank you Graeme! I finally got one imaginary freq and I believe it was both those issues you pointed to. Now I only need to converge it w.r.t displacements and include more surface atoms!

My apologies, I forgot to post the freq.dat: For displacement of 0.005:
857.231119 cm^{-1} ... 1
171.311052 cm^{-1} ... 1
85.785600 cm^{-1} ... 0
103.662689 cm^{-1} ... 0
136.663746 cm^{-1} ... 0
209.776436 cm^{-1} ... 0
238.833204 cm^{-1} ... 0
284.304291 cm^{-1} ... 0
318.386608 cm^{-1 ...

Hello Graeme and Andri,

Hope you are doing well!

I am trying to find the vib modes for a possible TS (CH3CHCOOH to CH3CCOOH) of dehydrogenation. The surface is a Ni[111] 5 layers and bottom two constrained. I obtained the saddle point from NEB followed by dimer calculations. The forces on the ...