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Probing the coupling of a dipole-bound electron with a molecular core.

ABSTRACT: A dipolar molecule can weakly bind an electron in a diffuse orbital. However, the spin-orbit coupling between this weakly bound electron and the electrons in the molecular core is not known. Here we probe this coupling using the linear C₂P^- anion with the ³Σ⁺ ground state, which possesses dipole-bound excited states because neutral C₂P (²Π) has a sufficiently large dipole moment. Photodetachment spectroscopy and resonant photoelectron spectroscopy are used to probe the nature of the dipole-bound states. Two dipole-bound excited states are observed with a binding energy of 37 cm^-1, corresponding to the two spin-orbit states of neutral C₂P (²Π_1/2 and ²Π_3/2). The current study demonstrates that the weakly bound electron in the dipole-bound excited states of C₂P^- is not spin-coupled to the electrons in the C₂P core and can be considered as a quasi-free electron.

SUBMITTER: Czekner J

PROVIDER: S-EPMC6354839 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Probing the coupling of a dipole-bound electron with a molecular core.

Czekner Joseph J Cheung Ling Fung LF Kocheril G Stephen GS Wang Lai-Sheng LS

Chemical science 20181115 5

A dipolar molecule can weakly bind an electron in a diffuse orbital. However, the spin-orbit coupling between this weakly bound electron and the electrons in the molecular core is not known. Here we probe this coupling using the linear C2P- anion with the 3Σ+ ground state, which possesses dipole-bound excited states because neutral C2P (2Π) has a sufficiently large dipole moment. Photodetachment spectroscopy and resonant photoelec ...[more]

PMID: 30809355

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