Hybrid orbitals table

Table 7.4 summarizes all we have said about hybrid orbitals and also describes their geometry. Note that—... 

Trends in Au-X and Au-P bond lengths in complexes (PPh3) AuX should be noted (Table 4.10) the Au-Cl bond length varies more with changes in coordination number than does the Au-P bond and is, therefore, more sensitive to the decrease in s character as the hybrid orbitals used by gold change from sp to sp3. 

Table 3.2 summarizes the relation between electron arrangement and hybridization type. No matter how many atomic orbitals we mix together, the number of hybrid orbitals is always the same as the number of atomic orbitals with which we started ... 

Bond distances for some important bond types are given in Table 1.5. As can be seen in this table, carbon bonds are shortened by increasing s character. This is most often explained by the fact that, as the percentage of s character in a hybrid orbital increases, the orbital becomes more like an s orbital, and hence is held more tightly by the nucleus than an orbital with less s character. However, other explanations have also been offered (see p. 37), and the matter is not completely settled. 

The s d and s p d hybrid orbital sets complete our survey of the common chemical geometries. Table 10-1 summarizes the results. Example completes this section of the Chapter. 

Table 3.2 Examples of Hybrid Orbitals Used to Describe Equivalent Bonds...

Table 16.3 Hybrid Orbital Types in Coordination Compounds. ...

In view of the number and types of hybrid orbitals that are exhibited by ions of the transition metals when complexes are formed, it is possible to arrive at a summary of the most important types of complexes that each metal ion should form. Although there are many exceptions, the summary presented in Table 16.5 is a useful starting point for considering the types of complexes that are formed by metals in the first transition series. 

The VSEPR notation for the Cl2F+ ion is AX2E3. According to Table 11.1, molecules of this type exhibit an angular molecular geometry. Our next task is to select a hybridization scheme that is consistent with the predicted shape. It turns out that the only way we can end up with a tetrahedral array of electron groups is if the central chlorine atom is sp3 hybridized. In this scheme, two of the sp3 hybrid orbitals are filled, while the remaining two are half occupied. 

Table 2 Molecules formed using hybrid orbitals in their bond formation.

For the acetylene molecule, the sp hybrid orbital is formed by combining one 2s orbital and one 2p orbital to form two sp orbitals. Each C atom uses one sp orbital to bond to one Is from H, and the other sp orbital to bond to the other C. The C=C triple bond is formed by the addition of two tt bonds by the overlap of two 2p orbitals from each C. Some of the properties of these hybrid bonds are shown in table 4.13. 

We see immediately that the standard tableaux function invariant to the hybrid angles, is actually the largest term in r/", but not overwhelmingly so. The others all depend on the hybrid angles and, therefore, so does 7). We may also note that using hybrid orbitals has a lower energy by 3 eV, but, as seen from Table 13.1,... 

Table 3.13. Energies for various hybrid orbital calculations of D d < nd D h ethane.

Table 16.7. The leading HLSP functions for the ground state wave function of C Hg at the equilibrium geometry when hybrid orbitals are used.

One way in which the n bonds in these compounds may be examined is by calculating natural bond orbitals (NBO) from the molecular wave function." Here, the MOs are localized, and the nature of the localized orbitals may be examined. The p-n localized orbital is found to have decreased occupation as the carbon-carbon bond is distorted, indicating that the p orbitals are being used in part in forming other localized orbitals (i.e., rehybridized). It is also possible to calculate natural hybrid orbitals, and their deviation from the line of centers between the atoms involved. The deviations are included in Table 15.2, and are seen to increase markedly with increased twisting. 

A simple orbital pieture can be used to deseribe these distortions. The lone pair ean oeeupy either an sp hybridized orbital or an unhybridized s orbital. Around eations from the upper half of the periodie table it usually oeeupies an sp orbital where the four valence-shell eleetron pairs (three bonding and one lone pair) are arranged at the corners of a tetrahedron giving rise to three primary bonds as described by the VSEPR model. Cations from lower in the table ean also show this configuration but are sometimes found with the lone pair oeeupying a pure s orbital which can then be treated as part of the core, giving a spherieally symmetric electron density. Intermediate states of hybridization are also possible and frequently found. 

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