I have been recently reading a lot on the quantum mechanical theory regarding Density Functional Theory, DFT, and Time Dependent Density Functional Theory, TDDFT (Oscillatory and Rotatory Strengths in particular) in order to understand how first principle calculations fundamental theory work.

I get that DFT is used to calculate the ground-state configuration of a system and TDDFT gets you the excited states useful for spectra determination and that there have been developed several algorithms in order to make calculations more efficient (timewise).

But I still can't answer myself in a short way how does each one works (math aside).

If you were to explain them to a person that is not necessarily familiar with quantum mechanics, how would you do it?

  • $\begingroup$ I do not have access, but if memory serves, this may help you: pubs.acs.org/doi/abs/10.1021/cr0505627 $\endgroup$ – TAR86 Jan 13 '20 at 19:13
  • $\begingroup$ @TAR86 Well then, iopenshell.usc.edu/chem545/lectures2014/HEAD_GORDON_REV.pdf $\endgroup$ – Buttonwood Jan 20 '20 at 21:05
  • $\begingroup$ Thank you both, that is indeed a great review on ab initio methodologies, still, a simple how and why does it works answer is still yet to be found $\endgroup$ – C. Alexander Jan 21 '20 at 15:41
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    $\begingroup$ I'm closing this question because it has been asked and answered on Physics Stack Exchange. Please note that Cross-Posting is highly discouraged on the network. $\endgroup$ – Martin - マーチン Feb 12 '20 at 10:21
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    $\begingroup$ While this might be true, it does not change the fact that the question was cross-posted, which is highly discouraged. Also the audience for these questions on our network will be very similar, hence the interested users will be redirected towards the question, which has the most information. If the question can be reshaped to highlight the different perspectives of the different communities, then the users may be persuaded to reopen this question. If you seek further clarification, please ask on Chemistry Meta. $\endgroup$ – Martin - マーチン Feb 13 '20 at 23:55