Identical particles exchange symmetry and the electric dipole moment in molecules

Guglielmo M. Tino

doi:10.3390/sym14112397

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arXiv · 2112.05342

Identical particles exchange symmetry and the electric dipole moment in molecules

Guglielmo M. Tino

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Abstract

Based on fundamental symmetries, molecules cannot have a permanent electric dipole moment although it is commonly used in the literature to explain the different molecular spectra for heteronuclear and homonuclear molecules. Electric-dipole rotational and vibrational spectra can indeed be observed in heteronuclear molecules while they are missing in molecules with identical nuclei. I show that the missing spectral features can be explained as an effect of the exchange symmetry for identical particles.

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Guglielmo M. Tino. 2021-12-10. Identical particles exchange symmetry and the electric dipole moment in molecules. https://doi.org/10.3390/sym14112397

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