Systematic calculation of molecular vibrational spectra through a complete Morse expansion

Abstract

We propose an accurate and efficient method to compute vibrational spectra of molecules, based on exact diagonalization of an algebraically calculated matrix based on powers of Morse coordinate. The present work focuses on the 1D potential of diatomic molecules: as typical examples, we apply this method to the standard Lennard-Jones oscillator, and to the ab initio potential of the H2 molecule. Global cm-1 accuracy is exhibited through the H2 spectrum, obtained through the diagonalization of a 30 x 30 matrix. This theory is at the root of a new method to obtain globally accurate vibrational spectral data in the context of the multi-dimensional potential of polyatomic molecules, at an affordable computational cost.

30 pages including 6 figures

References in corpus (3)

• Supersymmetry and Quantum Mechanics
• Time evolution in the Morse potential using supersymmetry: dissociation of the NO molecule
• Low-energy unphysical saddle in polynomial molecular potentials

Cited by in corpus (6)

• Thermodynamic properties of diatomic molecules systems under anharmonic Eckart potential
• Algebraic-matrix calculation of vibrational levels of triatomic molecules
• An optimized algebraic basis for molecular potentials
• Degeneracy and coherent states of the two-dimensional Morse potential
• Coherent states of the two-dimensional non-separable supersymmetric Morse potential
• A Note on Deformed Ladder Operators for Noncommutative Morse Oscillator