Ginzburg-Landau theory of the cluster glass phase
  On the basis of a recent field theory for site-disordered spin glasses a Ginzburg-Landau free energy is proposed to describe the low temperatures glassy phase(s) of site-disordered magnets. The prefactors of the cubic and dominant quartic terms change gradually along the transition line in the concentration-temperature phase diagram. Either of them may vanish at certain points $(c_*, T_*)$, where new transition lines originate. The new phases are classified 
Th. M. Nieuwenhuizen (UVA Amsterdam), C. N. A. van Duin (RUL Leiden)