Molecules

van der Waals Force, Dipole-Dipole Interaction

		Such familiar aspects of the behavior of matter in bulk as friction, surface tension, viscosity, adhesion, cohesion, and so on also arise from van der Waals forces. The interaction is between dipole-dipole. It can be the interaction between a permanent and an induced dipole as shown in Figure 12-17 or between a time average dipole (due to fluctuations of charge) and an induced dipole as shown in Figure 12-18. The van der Waals interaction is about 10 times weaker than hydrogen bond. The stronger hydrogen bond can be considered as interaction between permanent dipoles.
Figure 12-17 van der Waals Interaction [view large image]	Figure 12-18 van der Waals, Nonpolar [view large image]

Go to Next Section
 or to Top of Page to Select
 or to Main Menu