Ethoxide electrostatic potential map

FIGURE 19.3 The free W energies of ionization of ethanol and acetic acid in water. The electrostatic potential maps of ethoxide and acetate ion show the concentration of negative charge in ethoxide versus dispersal of charge in acetate. The color ranges are equal in both models to allow direct comparison. 

Display electrostatic potential maps for the conjugate bases of the acids above (hydroxide, ethoxide, formate and propionate anions), and examine the value of the electrostatic potential at the most electron-rich site. What causes a larger change in electrostatic potential, switching the alkyl group for H, or changing the structure of the functional group ... 

The electrostatic potential maps for the acetate and the ethoxide ions ... 

Figure 3.9 Calculated electrostatic potential maps for acetate anion and ethoxide anion. Although both molecules carry the same -1 net charge, acetate stabilizes the charge better by dispersing it over both oxygens.

Figure 18.3 uses electrostatic potential maps to compare the localized negative charge in ethoxide ion with the delocalized charge in acetate. 

The negative charge in ethoxide (a) is localized on oxygen. Electron delocalization in acetate (t>) causes the charge to be shared between two oxygens. The color scale is the same in both electrostatic potential maps. 

Electrostatic potential map of (a) acetate ion and (b) ethoxide ion. Note the negative (red) character for both oxygens in (a). 

Electrostatic potential maps of tert-butoxide and ethoxide. 

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