Critical behavior of the S=3/2 antiferromagnetic Heisenberg chain
  Using the density-matrix renormalization-group technique we study the long-wavelength properties of the spin S=3/2 nearest-neighbor Heisenberg chain. We obtain an accurate value for the spin velocity v=3.8+- 0.02, in agreement with experiment. Our results show conclusively that the model belongs to the same universality class as the S=1/2 Heisenberg chain, with a conformal central charge c=1 and critical exponent eta=1 
K. Hallberg, X.Q.G. Wang, P. Horsch and A. Moreo