Theoretical Study on the Photoelectron Spectra of
Ln(COT)<sub>2</sub><sup>–</sup>: Lanthanide Dependence of the
Metal–Ligand Interaction
Erika Nakajo
Tomohide Masuda
Satoshi Yabushita
10.1021/acs.jpca.6b10930.s001
https://acs.figshare.com/articles/journal_contribution/Theoretical_Study_on_the_Photoelectron_Spectra_of_Ln_COT_sub_2_sub_sup_sup_Lanthanide_Dependence_of_the_Metal_Ligand_Interaction/4246715
We
have performed a theoretical analysis of the recently reported
photoelectron (PE) spectra of the series of sandwich complex anions
Ln(COT)<sub>2</sub><sup>–</sup> (Ln = La–Lu, COT = 1,3,5,7-cyclooctatetraene),
focusing on the Ln dependence of the vertical detachment energies.
For most Ln, the π molecular orbitals, largely localized on
the COT ligands, have the energy order of e<sub>1g</sub> < e<sub>1u</sub> < e<sub>2g</sub> < e<sub>2u</sub> as in the actinide
analogues, reflecting the substantial orbital interaction with the
Ln 5d and 5p orbitals. Thus, it would be expected that the lanthanide
contraction would increase the orbital interaction so that the overlaps
between the COT π and Ln atomic orbitals tend to increase across
the series. However, the PE spectra and theoretical calculations were
not consistent with this expectation, and the details have been clarified
in this study. Furthermore, the energy level splitting patterns of
the anion and neutral complexes have been studied by multireference
ab initio methods, and the X peak splittings observed in the PE spectra
only for the middle-range Ln complexes were found to be due to the
specific interaction between the Ln 4f and ligand π orbitals
of the neutral complexes in e<sub>2u</sub> symmetry. Because the magnitude
of this 4f–ligand interaction depends critically on the final
state 4f electron configuration and the spin state, a significant
Ln dependence in the PE spectra is explained.
2016-11-02 00:00:00
e 2
5 p orbitals
Ln 4 f
Ln dependence
interaction
COT
X peak splittings
PE spectra
e 1 g
multireference ab initio methods
state 4 f electron configuration
ligand π orbitals
e 2 g
energy level splitting patterns