A CN bond is strongly polarized towards nitrogen ( the electronegativities of C and N are 2.55 and 3.04, respectively ) and subsequently molecular dipole moments can be high : cyanamide 4.27 D, diazomethane 1.5 D, methyl azide 2.17, pyridine 2.19 . For this reason many compounds containing CN bonds are water-soluble.
22.
The quasi-crystals have external shape of submicron globules and their internal structure consists of crystals enveloped by an amorphous matter ( see Fig . 1 ) . The crystals are formed by self-assembled stacks of the merocyanine molecular dipoles aligningthemselves in a parallel manner, while amorphous envelopes consist of thesame merocyanine dipoles aligned in an anti-parallel manner ( Fig . 1, Scheme2 ).
23.
For diatomic molecules there is only one ( single or multiple ) bond so the bond dipole moment is the molecular dipole moment, with typical values in the range of 0 to 11 D . At one extreme, a symmetrical molecule such as chlorine,, has zero dipole moment, while near the other extreme, gas phase potassium bromide, KBr, which is highly ionic, has a dipole moment of 10.5 D.
