Comment on 'Solutions of the Yang-Baxter equation for isotropic quantum spin chains'

Abstract

We comment on a recent paper by Kennedy (J. Phys. A: Math. Gen. 25 (1992) 2809) in which a systematic search for integrable spin-S su(2)-invariant quantum chains for S<or=6 revealed four spin-S families of integrable chains along with an additional integrable chain at S=3. We identify these su(2)-invariant chains with known G-invariant R-matrices, where G is a simple Lie algebra, and give arguments that Kennedy's results may well constitute the complete classification of integrable spin-S su(2)-invariant chains.