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arXiv · 1610.01820

Electronic ground state of Ni$_2^+$

V. Zamudio-Bayer·R. Lindblad·C. Bülow·G. Leistner·A. Terasaki·B. v. Issendorff·J. T. Lau
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Abstract

The $^{4}Φ_{9/2}$ ground state of the Ni$_2^+$ diatomic molecular cation is determined experimentally from temperature and magnetic-field-dependent x-ray magnetic circular dichroism spectroscopy in a cryogenic ion trap, where an electronic and rotational temperature of $7.4 \pm 0.2$ K was reached by buffer gas cooling of the molecular ion. The contribution of the magnetic dipole term to the x-ray magnetic circular dichroism spin sum rule amounts to $7\, T_z = 0.17 \pm 0.06$ $μ_B$ per atom, approximately 11 % of the spin magnetic moment. We find that, in general, homonuclear diatomic molecular cations of $3d$ transition metals seem to adopt maximum spin magnetic moments in their electronic ground states.

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V. Zamudio-Bayer, R. Lindblad, C. Bülow, G. Leistner, A. Terasaki, B. v. Issendorff, J. T. Lau. 2017-12-15. Electronic ground state of Ni$_2^+$. https://doi.org/10.1063/1.4967821

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