Realistic $\mathrm{SU(3)_c \otimes SU(3)_L \otimes U(1)_X}$ model with a   type II Dirac neutrino seesaw mechanism
  Here we propose a realistic $\mathrm{SU(3)_c \otimes SU(3)_L \otimes U(1)_X}$ electroweak gauge model with enlarged Higgs sector. The scheme allows for the natural implementation of a type II seesaw mechanism for Dirac neutrinos, while charged lepton and quark masses are reproduced in a natural way thanks to the presence of new scalars. The new $\mathrm{SU(3)_c \otimes SU(3)_L \otimes U(1)_X}$ energy scale characterizing neutrino mass generation could be accessible to the current LHC experiments. 
Mario Reig, Jose W.F. Valle, C.A. Vaquera-Araujo
hep-ph