1000 Basis functions limitation - Gaussian 09?

In summary, the person is asking if there is a limitation on the number of basis functions for frequency calculation in Gaussian 09. They have tried two calculations with different numbers of basis functions but were unable to complete the one with 1047 basis functions. They have searched for solutions online but have not found any. They are open to using a different program.
  • #1
akonhell
2
0
Does anyone know if there is a limitation of the number of basis functions for freq calculation in Gaussian 09?

I have 2 freq calculations, one has 879 basis functions and the other one has 1047 basis functions. Gaussian 09 couldn't finish the 1047 basis function calculation no matter how much memory I gave the job.

Here is my input file

%nprocshared=1
%rwf=Mol1.rwf
%nosave
%mem=31GB
%chk=Mol1.chk
#p freq=noraman rb3lyp scrf=(check,solvent=methanol) nosymm guess=tcheck chkbas genchk geom=allcheck

I'd optimized the molecule at the same level of theory, so I used the check point file to do freq calculation and every time, I get 2070 link die message. There is no additional useful error message in the output file...The last line in the output file is:

" Leave Link 1110 at Sat Jul 12 17:32:22 2014, MaxMem= 1744830464 cpu: 3662.0"

I've searched Google and the forum for an answer to my question, but it didn't seem I could find it. I've been working on this calculation and other calculations in the past couple months, but this one calculation just keep holding me off, or every time I need freq calculation of more than 1000 basis function, I hit this brick wall.

I appreciate any input/ thought to this question!

Cheers!
A
 
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  • #2
1. This is not a quantum physics question (in fact, it is not a physics question at all).
2. Just use a different program. Gaussian used to be a reasonable choice, but its technology is now >10 years behind the competition.
 
  • #3
Thanks cgk! I'll try to move this to the appropriate section.

A
 

1. What is the 1000 basis functions limitation in Gaussian 09?

The 1000 basis functions limitation in Gaussian 09 refers to the maximum number of basis functions that can be used in a single calculation. This limit includes both Cartesian and spherical basis functions and applies to all types of calculations, including optimization, frequency analysis, and reaction pathway calculations.

2. Why is there a limitation on the number of basis functions in Gaussian 09?

The limitation on the number of basis functions in Gaussian 09 is due to memory and computational constraints. As the number of basis functions increases, so does the required memory and computational resources, which can significantly impact the performance and accuracy of the calculation.

3. Can the 1000 basis functions limitation be exceeded in Gaussian 09?

No, the 1000 basis functions limitation cannot be exceeded in Gaussian 09. Attempting to use more than 1000 basis functions will result in an error message and the calculation will not be executed.

4. How does the 1000 basis functions limitation affect the accuracy of calculations in Gaussian 09?

The 1000 basis functions limitation can affect the accuracy of calculations in Gaussian 09 because it limits the level of theory that can be used. More complex systems may require a larger number of basis functions to accurately describe the electronic structure, and the limitation may result in less accurate results for these systems.

5. Are there any workarounds for the 1000 basis functions limitation in Gaussian 09?

Yes, there are some workarounds for the 1000 basis functions limitation in Gaussian 09. One option is to use a smaller basis set and employ basis set extrapolation techniques to improve the accuracy of the results. Another option is to use a different software that does not have this limitation, such as Gaussian 16 or ORCA.

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