A local algebraic approach to describe vibrational excitations of molecules
presenting both local and normal mode behaviors is presented. This approach allows the
connection with configuration space to be established. The model consists in expanding
the kinetic energy as well as the potential in terms of coordinates and momenta. An
algebraic representation is obtained by introducing creation and destruction bosonic operators
associated with the harmonic oscillators. From the resulting Hamiltonian a local algebraic
representation is obtained through a canonical transformation to local bosonic operators. Finally
an anharmonization is carried out by changing the local bosonic operators to ladder operators
associated with the Morse or P¨oschl-Teller functions. Since the model is connected with
configuration space, non linear curvilinear coordinates are contemplated. Our model is applied
to the vibrational spectroscopic description of the 12C16O2 molecule. The eigenstates are tested
by calculating the derivatives for the polarizability for this molecule.