All Questions
Tagged with density-functional-theory orbitals
5 questions
2
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Exploiting 8-fold symmetry of ERI tensor for building Coulomb and Exchange matrices
I'm trying to write a restricted Hartree Fock code in Fortran that reads in a file of zeroth-iteration 1 and 2 electron integrals (FCIDUMP format) and uses them to do the SCF procedure from an initial ...
- 21
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What are the rules for constructing Kohn-Sham orbitals?
I just recently began to study quantum chemistry and need some clarification for the construction of Kohn-Sham orbitals.
Consider a system of several atoms. Let there be $N$ electrons in this system.
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- 117
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Is Tkatchenko's MBD-NL method self-consistent?
I have a question regarding Tkatchenko's [1] new nonlocal many-body dispersion method (MBD-NL). Does anyone know if it's a self-consistent method? I read this paper many times but I'm still not sure.
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Strange "far out" orbitals in HF and DFT calculations. Why do they occur?
I calculated some orbitals and I get quite strange results with orbital geometries I wouldn't expect from MO theory. A more experienced colleague just said: "That's always the case with big basis sets,...
- 5,802
61
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Striking examples where Kohn-Sham orbitals clearly have no physical meaning
In Density Functional Theory courses, one is often reminded that Kohn-Sham orbitals are often said to bear no any physical meaning. They only represent a noninteracting reference system which has the ...
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