The effect of long-range three-body forces on the elastic constants of the inert gas solids at the absolute zero

The elastic constants C 11 , C 12 and C 44 of neon, argon, krypton and xenon are calculated at the absolute zero. One calculation is made assuming only two-body interactions. A second calculation is then presented in which the triple-dipole interaction of Axilrod and Teller is included. It is shown that the quantity B = ( C 44 - C 12 / C 12 , which is always positive when calculated with only two-body forces, is reduced when the triple-dipole interaction is included. In the cases of argon, krypton and xenon B in fact becomes negative. It should be possible to test this experimentally and if B were found negative this would provide strong evidence for the existence of three-body forces.