increasing the number of atomic orbitals used in the Mulliken analysis.

[Mhmd Al ahmad]

Dear DIRAC experts.

I'm trying to perform a Mulliken analysis using the ZORA Hamiltonian for the AuK^(-) molecule. In the output file, we find

*** Total gross population ***

Gross      Total    |    L Au  1        L K   1    
-----------------------------------------------------
 total    98.47738  |     79.14537       19.33200

One would expect to see 99 instead of 98.47738. On the DIRAC website we can see: "In the case of a large polarization contribution, one can either increase the number of atomic orbitals used in the analysis or..." Practically, how can we increase the number of atomic orbitals used in the analysis?

best regards
Mohamed

[Trond SAUE]

Dear Mohamed,

you are apparently reading here

https://www.diracprogram.org/doc/release-23/tutorials/analysis/projection_analysis.html

but those pages concern projection analysis, not Mulliken population analysis.

You have chosen to use the ZORA Hamiltonian

https://www.diracprogram.org/doc/release-23/manual/hamiltonian.html#approximate-2-component-hamiltonians

but please note what is written

Please note that these are only tested for energies and generally do not work for properties !

All the best,

    Trond

--

Trond Saue
Laboratoire de Chimie et Physique Quantiques
UMR 5626 CNRS --- Université Toulouse III-Paul Sabatier
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