  We report the presence of spin dimerization in the ground state of the one
dimensional Kondo lattice model at quarter filling. The emergence of this new
phase of the Kondo lattice can be traced to the form of the RKKY interaction
between the localized moments and provides the first example of dimerization
induced indirectly by itinerant electrons. We propose this dimer ordering as
the driving mechanism of the spin-Peierls phase observed in the
quasi-one-dimensional organic compounds (Per)$_{2}$M(mnt)$_{2}$ (M=Pt, Pd).
Moreover, this suggests that a richer phase diagram than the Doniach paradigm
may be needed to accommodate the physics of heavy fermion materials.
