UT theoretical chemistry code forum

Hi!

I simulated a CO molecule adsorbing onto the MnO surface (with C on top of Mn) using IBRION = 5 and NFREE = 2. And I got 6 frequencies in the OUTCAR:

1 f = 61.660865 THz 387.426644 2PiTHz 2056.785017 cm-1 255.008933 meV
2 f = 4.306939 THz 27.061296 2PiTHz 143.664019 cm-1 17.812075 meV
3 f = 3 ...

Hi! I was carrying out dynamic matrix calculation on a simple molecule CO and I have obtained the following frequencies:

695.430122 cm^{-1} ... 1
24.663956 cm^{-1} ... 1
0.000005 cm^{-1} ... 1
0.000004 cm^{-1} ... 0
60.734582 cm^{-1} ... 0
1614.673958 cm^{-1} ... 0

So which of these ...

Hi. I have changed value of ICHAIN from 0 to 1. But the calculation still gives me all 0 frequencies. Are there additional problems with my code? Should the atoms in POSCAR all set to "T" or "F" for this to work?

Many thanks

I have tried to carry out a dynamic matrix calculation of a simple carbon monoxide molecule (CO), in an attempt to figure out its zero point energy (ZPE). I have carried out many attempts but the frequencies I got from using dymmatrix.pl were always all 0. It's the first time I'm doing a dynamic ...