Take a look at all the following molecules: $\ce{SO3^{2-}}$, $\ce{SO2}$, $\ce{SO4^2-}$, $\ce{PF5}$ and many more you can add. In all these there is a controversy of one of these two types:

  1. Is formal charge more important than octet rule - as to justify hypervalency- on determining Lewis structure? As a rule I'd say the answer is no. For example in $\ce{SO2}$,$\ce{SO3}$, $\ce{SO4^2-}$, Do calculations show it?

  2. What is the central atom hybridization? For example, in $\ce{PF5}$ (see here). Does it involve d-orbitals?

In any case, both previous statements are related to the d-orbitals energy.

There is -at least- one straightforward way to answer the question:

  • Calculate* the Molecular Orbitals and see which of previous options fit better (the use of d-orbitals or the non use of them). *sure some can be found in some papers.

So the question is:

Are there theoretical studies of many concrete examples as to remark that d orbitals don't play any relevant role in covalent bonding?


closed as too broad by Mithoron, A.K., Tyberius, Todd Minehardt, Karl Sep 27 '18 at 20:25

Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer. Avoid asking multiple distinct questions at once. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • $\begingroup$ Sorry, can you clarify your question? What info are you looking for that is not in the related posts? $\endgroup$ – Greg Sep 24 '18 at 16:15
  • $\begingroup$ @Greg look at the title, I think the posts below show $d$ orbitals are not important in covalent bonds. I ask what is the Evidence. $\endgroup$ – santimirandarp Sep 24 '18 at 17:20
  • 2
    $\begingroup$ Some related pub.: 1. Gillespie, R. Coord. Chem. Rev. 2002, 233-234, 53–62. DOI: 10.1016/S0010-8545(02)00102-9 2. Gillespie, R. Inorg. Chem. 1995, 34 (4), 978–979. DOI: 10.1021/ic00108a032 3. Smith, D. J. Chem. Educ. 2005, 82 (8), 1202. DOI: 10.1021/ed082p1202 4. Jensen, W. J. Chem. Educ. 2006, 83 (12), 1751. DOI: 10.1021/ed083p1751 5. Halgren, T. J. Am. Chem. Soc. 1977, 99 (21), 6793–6806. DOI: 10.1021/ja00463a002 $\endgroup$ – Martin - マーチン Sep 25 '18 at 13:58
  • $\begingroup$ Is this only meant to be about supposedly hypervalent compounds of main group elements? $\endgroup$ – orthocresol Sep 25 '18 at 20:14
  • $\begingroup$ Why don't you look for studies that do show a significant d orbital contribution to covalent bonding. Proving nonexistence is hard. $\endgroup$ – Karl Sep 27 '18 at 20:28