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My textbook says:

It is appropriate to remark that the trick of rationalizing apparent violations of the octet rule by invoking the participation of d-orbitals in the bonding scheme is a matter of some controversy. Some scientists feel that the d-orbitals lie so high in energy that they should not be treated as valence orbitals, but as excited orbitals which cannot confer any appreciable stability to chemical bonds. Others feel that while d-orbitals are of high energy in free atoms, their energy decreases as other atoms approach to make bonds.

This author has not been convinced of the absolute validity of either side of this argument, and interprets the controversy merely as more evidence that the description of chemical bonds in terms of a few atomic orbitals is a highly approximate procedure. The most convincing reason for invoking d-orbitals in chemical bonding is that it is a simple idea which works, if it is used carefully and not over-interpreted.

Since this book is quite an old edition, I wanted to know whether there are any newer developments in this direction. Which of the two views is generally acceptable?

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    Surely they can. Even f-orbitals do so, see e.g. this question and references therein. – Wildcat Jul 11 '15 at 15:48
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  • Text in this book is about hypervalence of p-block and is all right. In d-block it's the other way round - d orbitals are used – Mithoron Jul 11 '15 at 16:42
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    this may answer it http://chemistry.stackexchange.com/a/5242/9961 – Mithoron Jul 11 '15 at 17:04
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    Are you specifically interested in d-orbital participation in hypervalent/expanded octet compounds or are you looking for example of d-orbital bonding in general. If it is the former then there have been a number of excellently answered questions on this topic before. Here and here are good places to start. – bon Jul 11 '15 at 17:56
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    Mmmm. Let me put it this way: the results of QC calculations for main group compounds are more precise if we include d-orbitals in used basis set. However, the resulting orbitals have only minor d-characters. Still, use of d-orbitals in the basis set is critical for chemically precise results, since said results are usually a difference of two large values, so even a small relative improvement of precision may have significant impact on the results. – permeakra Jul 11 '15 at 19:39
  • @permeakra The d-orbitals you are talking about and their contributions are usually polarisation functions, their inclusion is important even in single-determinant methods. That doesn't mean that they represent the vacant d-orbitals of the main group elements. Also their contribution is usually below 1% for these. – Martin - マーチン Sep 24 '18 at 16:41

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Yes it works, according to result they have with organometallic chemistry. You may not know $e_g$ and $t_{2g}$ orbitals. Have a look at this diagram of orbitals :

Its diagram for an octaedric complex, where M is the metal. Positions of $e_g$ and $t_{2g}$ depends of what L is.

enter image description here

ParaH2
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