The complete conformal spectrum of a sl(2|1) invariant network model and logarithmic corrections

We investigate the low temperature asymptotics and the finite-size spectrum of a class of Temperley-Lieb models. As reference system we use the spin-1/2 Heisenberg chain with anisotropy parameter Delta and twisted boundary conditions. Special emphasis is placed on the study of logarithmic corrections appearing in the case of Delta = 1/2 in the bulk susceptibility data and in the lowenergy spectrum yielding the conformal dimensions. For the sl(2 vertical bar 1) invariant 3-state representation of the Temperley-Lieb algebra with Delta = 1/2 we give the complete set of scaling dimensions, which show huge degeneracies.