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arXiv · 0904.4366

Rotation and vibration of diatomic molecule in the spatially-dependent mass Schrodinger equation with generalized q-deformed Morse potential

Abstract

The analytic solutions of the spatially-dependent mass Schrodinger equation of diatomic molecules with the centrifugal term l(l+1)/r2 for the generalized q-deformed Morse potential are obtained approximately by means of a parametric generalization of the Nikiforov-Uvarov (NU) method combined with the Pekeris approximation scheme. The energy eigenvalues and the corresponding normalized radial wave functions are calculated in closed form with a physically motivated choice of a reciprocal Morse-like mass function, m(r)=m0/(1-deltae^{-a(r-r_{e})})2, 0<delta<1, where a and r_{e} are the range of the potential and the equilibrium position of the nuclei. The constant mass case when delta=0 is also studied. The energy states for H2, LiH, HCl and CO diatomic molecules are calculated and compared favourably well with those obtained by using other approximation methods for arbitrary vibrational n and rotational l quantum numbers.

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Sameer Ikhdair. 2009-04-28. Rotation and vibration of diatomic molecule in the spatially-dependent mass Schrodinger equation with generalized q-deformed Morse potential. https://doi.org/10.1016/j.chemphys.2009.04.023

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