Spinon attraction in spin-1/2 antiferromagnetic chains

We derive the representation of the two-spinon wave function for the Haldan e-Shastry model in terms of the spinon coordinates. This result allows us t o rigorously analyze spinon interaction and its physical effects. We show t hat spinons attract one another. The attraction gets stronger as the size o f the system is increased and, in the thermodynamic limit, determines the p ower law with which the susceptibility diverges.