Molecular vibrational states in the binary cold fission of $^{252}$Cf
  We predict a molecular vibrational state in the cold binary fission of $^{252}$Cf using a simple decay cluster model. The Hamiltonian of two even-even fragments in the pole-pole configuration is built in the same fashion as that for the dinuclear molecule formed in heavy-ions collisions. The interaction between the two fragments is described by the double-folding M3Y potential. The spectrum of the butterfly vibrations is derived and its dependence on fragments deformation and mass-assymetry is discussed. Some experimental implications are commented. 
S Misicu, A Sandulescu and W Greiner