The sign of the spin-orbit coupling constant in (t2)52t2 states of mx4+ ions

doi:10.1016/0009-2614(87)80485-2

Chemical Physics Letters

Volume 140, Issue 6, 23 October 1987, Pages 553-557

https://doi.org/10.1016/0009-2614(87)80485-2 Get rights and content

Abstract

It is shown that the sign of the spin-orbit coupling constant in ²T₂ states of MX⁺₄ molecular ions (M = C, Si, Ge; X = F, Cl, Br, I) arising from the (t₂)⁵ electron configuration can be positive, negative or even zero. Predominantly, the sign depends on the orientation of the p-orbitals on the four halogen atoms with respect to the M-X bonds. Experimentally observed splittings show that it is incorrect to describe the two highest t2 valence orbitals of MX₄ as pure pπ non-bonding and pure pσ bonding, since both exhibit pσ/pπ mixing. This is confirmed by semi-empirical SCF MNDO molecular-orbital calculations.

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The sign of the spin-orbit coupling constant in (t2)52t2 states of mx4+ ions

Abstract

Intern. J. Mass Spectrom. Ion Phys.

J. Chem. Soc. Faraday Trans. II

Trans. Faraday Soc.

Mol.Phys.

Acta Phys. Polon.

Mol. Phys.

Mol. Phys.

The sign of the spin-orbit coupling constant in (t₂)⁵²t₂ states of mx₄⁺ ions