“…Several infinite families of integrable open quantum spin chains with quantum group (QG) symmetry have recently been identified [1,2]. The transfer matrices for these models are constructed [3] from trigonometric R-matrices, which are associated to non-exceptional affine Lie algebrasĝ [4,5,6,7], and from certain K-matrices (also known as reflection matrices, or boundary S-matrices) depending on a discrete parameter p [8,9,10,11,12,13,2]. These transfer matrices have QG symmetry corresponding to removing the p th node from theĝ Dynkin diagram, as summarized in Tables 2 and 3.…”