Hydrogen bonding electronegativity

Two hydrogen-bonded electronegative atoms can approach each other more closely than the sum of their molecular radii. In other words, the intermolecular distance between B. .. H is less than the value expected from summing the two van der Waals radii of... 

In the next few sections, we describe the influence of a number of parameters aromatic resonance, lone-pair and dipolar repulsion, internal hydrogen bonding, electronegative substituents, and the surrounding solvent on the relative stability of tautomeric forms. The remainder of this chapter is devoted to a brief history of tautomeric equilibria and tautomer dynamics. 

Dipole-dipole interactions especially hydrogen bonding are present m amines but absent m alkanes But because nitrogen is less electronegative than oxygen an N—H bond IS less polar than an O—H bond and hydrogen bonding is weaker m amines than m alcohols... 

Hydrogen Bond Formation. This faciUtates adsorption if the mineral and the adsorbate have any of the highly electronegative elements S,0,N,F, and hydrogen. A weak (physical) bond is estabflshed between the sohd wall and the reagent through the alignment of the cited elements. 

Element Electronegativity Covalent radius, pm Usual coordination number Bond with hydrogen Bond length, pm Bond energy, kj/mot ... 

For most purposes, hydroearbon groups ean be eonsidered to be nonpolar. There are, however, small dipoles associated with C—H bonds and bonds between earbons of different hybridization or substitution pattern. For normal sp earbon, the earbon is found to be slightly negatively charged relative to hydrogen. The electronegativity order for hybridized carbon orbitals is sp > sp > sp. Scheme 1.1 lists the dipole moments of some hydrocarbons and some other organic molecules. 

Hydrogen bond (Section 2.13) A weak attraction between a hydrogen atom bonded to an electronegative atom and an electron lone pair on another electronegative atom. 

The hydrogen bond is a weak attractive force which operates between a proton and two electronegative atoms, such as... 

A comparison of these p/CHB values at constant pK of the bases reveals that the most important factor which determines the correlation between the structure and the hydrogen bonding ability depends on the electronegativity of the acceptor atom in the Lewis bases employed. Thus, the strength of the basicities of the oxygen compounds described above is... 

---