Dsp orbital

When more d orbitals are available, six stronger equivalent eigenfunctions with their maxima directed towards the comers of a trigonal prism of unit axial ratio can be formed1). The bond-strength of these is 2.985, nearly equal to the maximum 3.000 possible for dsp orbitals. 

Next, enantiopure silicon allylation reagent will be presented, which already inherits Lewis acidity. It is accepted that Lewis acidity of silicon, as well as its high tendency to expand valence shell, increases [59, 60] if it is tetravalent and incorporated into strained four- or five-membered ring systems (strain-release Lewis acidity) [61]. This corresponds to smaller energy gaps between sp and dsp orbitals of a strained system as compared to an acyclic species. 

That this interpretation is reasonable is indicated by a comparison with the octahedral radii of iron, cobalt, and nickel, indicated in Figure 11-9 by squares, with the oxidation numbers also shown. The smaller octahedral radii correspond to d2sp8 orbitals, with 33 percent d character, and the radii that are about 0.10 greater correspond to dsp orbitals, with 20 percent d character. It is evident that there is a rapid decrease in single-bond radius with increase in the amount of d character... 

The majority of ligands have a lone pair of electrons in a filled sp 1 type orbital that can overlap with a vacant metal dsp orbital, derived from the vacant d, p, and s orbitals of the metal, to form a conventional two-electron two-centre a bond. Ligands of this type increase the electron density on the central metal atom. This is the sort of bond that used to be called dative covalent and represented by an arrow. Nowadays it is more common to represent all bonding to metals of whatever kind by simple lines. 

Pauling suggested the water molecules could be co-ordinated as the spin-paired, square complex anion, [Re(H20)4]", with dsp orbitals ... 

This ion can, however, form a spin-paired, square 4-co-ordinated type of complex using dsp orbitals. 

M- 4 . - -L vacant "dsp" orbital filled lone pair on ligand... 

A, VB depiction of [NilCN) . B, Two lone 3d electrons pair up and free one 3d orbital for hybridization with the 4s and two of the 4p orbitals to form four dsp orbitals, which become occupied with lone pairs (red) from four CN ligands. 

The dsp hybridized phosphorus atom in the PCI5 molecule uses its five dsp orbitals to share electrons with the five chlorine atoms. Note that a set of five effective pairs around a given atom always requires a trigonal bipyramidal arrangement, which in turn requires dsp hybridization of that atom. 

Now we can describe the bonding in the PCI5 molecule shown in Fig. 9.22. The five P—Cl (7 bonds are formed by sharing electrons between a dsp orbital on the phosphorus atom and an orbital on each chlorine. 

A set of dsp hybrid orbitals on a phosphorus atom. Note that the set of five dsp orbitals has a trigonal bipyramidal arrangement. (Each cfsp orbital also has a small lobe that is not shown in this diagram.)... 

Note that the lone pairs are placed in the plane where they are 120 degrees apart. To accommodate five pairs at the vertices of a trigonal bipyramid requires that the xenon atom adopt a set of five dsp orbitals. Each fluorine atom has four electron pairs and... 

Five electron pairs (trigonal bipyramidal arrangement) requires dsp orbitals... 

The orbitals used to form the bonds in the PCI5 molecule. The phosphorus atom uses a set of five dsp orbitals to share electron pairs with sp orbitals on the five chlorine atoms. The other sp orbitals on each chlorine atom hold lone pairs. 

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