A study of N2O vibrational excitations in the framework of an algebraic approach

A study of the vibrational excitations of the 14 N 2 16 O molecule is presented. The description is based on a local algebraic model with dynamical algebra s u 1 ( 2 ) ⊕ s u ( 3 ) ⊕ s u 2 ( 2 ) . The model starts in configuration space with a polyad-conserving Hamiltonian expanded in terms of normal coordinates. The algebraic representation is obtained through the usual bosonic realization of the normal modes. A local algebraic representation of the Hamiltonian is obtained considering a canonical transformation from normal to local bosonic operators, which are later mapped to S U ( 3 ) and S U ( 2 ) Morse ladder operators. First, a vibrational study was carried out taking the 183 experimental energies available in MARVEL using a Hamiltonian with 33 parameters obtaining rms = 0 . 46 cm −1 . An additional analysis was performed including a set of 261 vibrational levels recorded in MARVEL, with 32 parameters and deviation rms = 0 . 68 cm −1 . In addition, we address the procedure to calculate IR/Raman intensities. • The vibrational description of the N 2 O molecule is presented. • An effective Hamiltonian is proposed taking anharmonicities through the introduction of S U ( 2 ) Morse and U ( 3 ) operators. • A fit to 183 experimental levels provides a rms deviation of 0.46 cm −1 . • A fit including all the 261 energies recorded in MARVEL are considered with an rms = 0.68 cm −1 . • A procedure to calculate IR/Raman intensities is presented.