Dear Manal, this warning is typical when Gaussian identifies low vibrational frequencies. As by default the rigid rotor harmonic oscillator approximation is being used this can sometimes lead to erroneous partition functions. In general it is good to check the frequencies, especially the low ones (<600 cm-1) by visualizing them with another software (i.e Gaussview) and check if they correspond to rotations, instead of vibrations. If this is the case, you can run again the frequency part of your calculation by refining the freq keyword: Freq=HinderedRotor This will treat the identified low frequency modes as rotations and not vibrations and in your Thermal output you will have corrected values of partition functions, S and H. Hope this helps
Dear Manal, this warning is typical when Gaussian identifies low vibrational frequencies. As by default the rigid rotor harmonic oscillator approximation is being used this can sometimes lead to erroneous partition functions. In general it is good to check the frequencies, especially the low ones (<600 cm-1) by visualizing them with another software (i.e Gaussview) and check if they correspond to rotations, instead of vibrations. If this is the case, you can run again the frequency part of your calculation by refining the freq keyword: Freq=HinderedRotor This will treat the identified low frequency modes as rotations and not vibrations and in your Thermal output you will have corrected values of partition functions, S and H. Hope this helps
Dear Manal, this warning is typical when Gaussian identifies low vibrational frequencies. As by default the rigid rotor harmonic oscillator approximation is being used this can sometimes lead to erroneous partition functions. In general it is good to check the frequencies, especially the low ones (<600 cm-1) by visualizing them with another software (i.e Gaussview) and check if they correspond to rotations, instead of vibrations. If this is the case, you can run again the frequency part of your calculation by refining the freq keyword: Freq=HinderedRotor This will treat the identified low frequency modes as rotations and not vibrations and in your Thermal output you will have corrected values of partition functions, S and H. Hope this helps
Dear Manal, this warning is typical when Gaussian identifies low vibrational frequencies. As by default the rigid rotor harmonic oscillator approximation is being used this can sometimes lead to erroneous partition functions. In general it is good to check the frequencies, especially the low ones (<600 cm-1) by visualizing them with another software (i.e Gaussview) and check if they correspond to rotations, instead of vibrations. If this is the case, you can run again the frequency part of your calculation by refining the freq keyword: Freq=HinderedRotor This will treat the identified low frequency modes as rotations and not vibrations and in your Thermal output you will have corrected values of partition functions, S and H. Hope this helps
You can look e.g. at Wong and Green paper, Mol.Phys. 103, 1027, 2005 and references therein.
You can look e.g. at Wong and Green paper, Mol.Phys. 103, 1027, 2005 and references therein.
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I found this warning message online, not sure if it helps
http://www.ccl.net/chemistry/resources/messages/2004/04/20.005-dir/
I found this warning message online, not sure if it helps
http://www.ccl.net/chemistry/resources/messages/2004/04/20.005-dir/
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Dear Manal,
this warning is typical when Gaussian identifies low vibrational frequencies.
As by default the rigid rotor harmonic oscillator approximation is being used
this can sometimes lead to erroneous partition functions.
In general it is good to check the frequencies, especially the low ones (<600 cm-1)
by visualizing them with another software (i.e Gaussview) and check
if they correspond to rotations, instead of vibrations.
If this is the case, you can run again the frequency part of your calculation by refining the freq keyword:
Freq=HinderedRotor
This will treat the identified low frequency modes as rotations and not vibrations
and in your Thermal output you will have corrected values of partition functions,
S and H.
Hope this helps
Dear Manal,
this warning is typical when Gaussian identifies low vibrational frequencies.
As by default the rigid rotor harmonic oscillator approximation is being used
this can sometimes lead to erroneous partition functions.
In general it is good to check the frequencies, especially the low ones (<600 cm-1)
by visualizing them with another software (i.e Gaussview) and check
if they correspond to rotations, instead of vibrations.
If this is the case, you can run again the frequency part of your calculation by refining the freq keyword:
Freq=HinderedRotor
This will treat the identified low frequency modes as rotations and not vibrations
and in your Thermal output you will have corrected values of partition functions,
S and H.
Hope this helps
More
VOTE
Dear Manal,
this warning is typical when Gaussian identifies low vibrational frequencies.
As by default the rigid rotor harmonic oscillator approximation is being used
this can sometimes lead to erroneous partition functions.
In general it is good to check the frequencies, especially the low ones (<600 cm-1)
by visualizing them with another software (i.e Gaussview) and check
if they correspond to rotations, instead of vibrations.
If this is the case, you can run again the frequency part of your calculation by refining the freq keyword:
Freq=HinderedRotor
This will treat the identified low frequency modes as rotations and not vibrations
and in your Thermal output you will have corrected values of partition functions,
S and H.
Hope this helps
Dear Manal,
this warning is typical when Gaussian identifies low vibrational frequencies.
As by default the rigid rotor harmonic oscillator approximation is being used
this can sometimes lead to erroneous partition functions.
In general it is good to check the frequencies, especially the low ones (<600 cm-1)
by visualizing them with another software (i.e Gaussview) and check
if they correspond to rotations, instead of vibrations.
If this is the case, you can run again the frequency part of your calculation by refining the freq keyword:
Freq=HinderedRotor
This will treat the identified low frequency modes as rotations and not vibrations
and in your Thermal output you will have corrected values of partition functions,
S and H.
Hope this helps
More
VOTE