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You can choose an avatar and change the default style by going to "Profile" → "Personality" or "Display".#1 2025-04-22 09:44:28
- David
- Member
- Registered: 2017-05-16
- Posts: 86
How to calculate more accurate atomic charges than Mulliken in Molcas?
I have a question regarding the calculation of atomic charges. After completing my CASSCF calculation, I can extract Mulliken charges from the rasscf.molden file. However, as is well known, Mulliken charges exhibit strong basis set dependence and may lack reproducibility.
Could anyone suggest alternative methods to compute more robust atomic charges (e.g., Löwdin, Natural Population Analysis, or Hirshfeld charges) within OpenMolcas? Are there specific keywords or modules that can be used for this purpose? Any guidance or example inputs would be greatly appreciated.
Last edited by David (2025-04-22 09:44:54)
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#2 2025-04-22 10:53:40
- Ignacio
- Administrator
- From: Uppsala
- Registered: 2015-11-03
- Posts: 1,129
Re: How to calculate more accurate atomic charges than Mulliken in Molcas?
You could try the ESPF module.
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#3 2025-08-06 14:03:00
- vkj
- Member
- Registered: 2019-04-10
- Posts: 31
Re: How to calculate more accurate atomic charges than Mulliken in Molcas?
I really think this is atype of questin that has no one good answer, the type of charges really depend on what you want to do with them , some are good for Dipole moment , some are good for ESP potentials etc. Anyways u can use Multiwfn to compute the charges from molcas molden files ( the rasscf.molden.$State files). Multiwfn has lot of charges implemented. You might have to preprocesss the molden file to create another molden file that is suitable for Multiwfn ( They mention this in the manual of Multiwfn)
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