CRC Press eBooks

The Rotator

Ahmad Amer

Published Nov 5, 2025• 0 citations

Abstract

This chapter examines the quantum mechanical rotator, a model that effectively approximates the behavior of a diatomic molecule when radial vibrations are negligible. The energy eigenvalues and the degeneracy of energy levels are derived through straightforward calculations. The s-state is presented as an example of a state with a constant probability density, independent of spatial coordinates. The p-state is also analyzed, and its eigenstates are interpreted to reveal the most probable particle trajectories. A qualitative comparison is made between these quantum predictions and the classical description of rotational motion. Metadata/Keywords: quantum rotator, diatomic molecule, energy eigenvalues, degeneracy, probability density, classical comparison, angular momentum

DOI: 10.1201/9781003677109-6

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