QUANTUM ALGEBRAIC DESCRIPTION OF VIBRATIONAL MOLECULAR-SPECTRA

Vibrational spectra of diatomic molecules can be described in terms of the q-deformed anharmonic oscillator. The Hamiltonian has the U(q)(2) superset-of O(q)(2) symmetry, where q is the parameter measuring its deviation from the usual U(2) superset-of O(2) symmetry. The energy formula obtained is equivalent to an expansion in terms of powers of (upsilon + 1/2), where upsilon is the vibrational quantum number, and corresponds to summing a Dunham expansion for vibrational molecular spectra.