An expression for three-body interactions in intermolecular forces. These dipole dispersion terms, called Axilrod-Teller terms (named after B. M. Axilrod and E. Teller, who discovered them in 1943) are of importance in the third virial coefficient. At low temperatures, the Axilrod-Teller terms can have a comparable size to two-body interactions, making them of importance to such properties of liquids as pressure and surface tension. The Axilrod-Teller formula for the dispersion energy V of three closed-shell atoms A, B, and C is given by V=– C6/rAB6 – C6/rBC6 – C6/rCA6+C′/(rABrBCrCA)3, where C6 is a coefficient depending on the identity of the atoms, C′ is a coefficient depending on another constant and the angles between the atoms, and the r terms give distances between the indicated atoms.
V=– C6/rAB6 – C6/rBC6 – C6/rCA6+C′/(rABrBCrCA)3