Promotion energies

The late-1980s also saw the initiation of more widespread programs operated by utilities to promote energy-efficient appliances in the marketplace. Many of these focused on reducing peak loads by offering rebates for more efficient air conditioners and chillers in both residential and commercial applications. 

Golove, W. H., and Eto, J. H. (1996). Market Barriers to Energy Efficiency A Critical Reappraisal of the Rationale for Public Policies to Promote Energy Efficiency. Lawience Berkeley National Laboratniy. LBNL-.38059. 

Table 1 describes the ensuing legislation that was promulgated to promote energy efficient construction as a result of the Arab oil embargo. 

The effective bond energy is assumed to be the product of S and a bond-energy parameter b, corrected by subtracting the terms y2Pd and 82Pf, in which Pd and Pf are the promotion energies for the d and/ terms ... 

The shear work done for one atomic (molecular) displacement, b is the applied force times the displacement, or xb3. This work must equal the promotion energy 2Eg. Therefore, letting b3 equal the molecular volume, Vm, the required shear stress is approximately 2Eg/Vm. The parameter [Eg/Vm] is called the bond modulus. It has the dimensions of stress (energy per unit volume). The numerator is a measure of the resistance of a crystal to kink movement, while the denominator is proportional to the work done by the applied stress when a kink moves one unit distance. Overall, the bond modulus is a measure of the shear strengths of covalent bonds. 

In the above picture, the primary factor that dictates allocation of hybrid p character toward electronegative ligands is the promotion energy Asp, the valence-shell s-p energy separation... 

Figure 3.19 illustrates the dependence of Asp on location in the periodic table for each of the first three elements of main groups 13-17. The promotion energy varies with group number in a manner similar to electronegativity (cf. Fig. 3.17). Although Asp is doubtless important, other factors (such as differences in orbital radii) appear to play a role in general spd hybridization.

Figure 3.19 The Asp = enp — ens valence-shell promotion energy for group 13-17 elements n = 2 (circles), n = 3 (squares), n = 4 (triangles). (enp is the average orbital energy of occupied valence p AOs of a spin.)...

Exceptions to the E.A.N. rule do occur, particularly with d8 metal ions, where many examples of square-planar, 16-electron complexes are known. In these complexes, the high-lying pz orbital is nonbonding and remains empty. This deviation from the rule is often said to be due to the large s-to-p promotion energies found for the free atoms. As the atomic number increases across a given transition-metal series, the... 

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