Hydrogen bond acceptance/electron pair surfaces

Our focus in this chapter shall be primarily upon the surface electrostatic potential, specifically its most positive and most negative values, denoted by Vs, max and Vs,min, respectively. There may be several local and absolute maxima and minima on a given surface. They indicate the most positive and negative sites. The former are often associated with hydrogens, especially acidic ones, and the latter with lone pairs, tt electrons of unsaturated molecules and strained bonds. We have demonstrated that Vs niax and Vs nim correlate well with measures of hydrogen bond donating and accepting tendencies . 

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