UV and IR Spectroscopy of Cryogenically Cooled, Lanthanide-Containing Ions in the Gas Phase

Inokuchi Yoshiya

Kaneko Masashi

Honda Takumi

Nakashima Satoru

Ebata Takayuki

Rizzo Thomas R.

Inorganic Chemistry

We measure UV and IR spectra in the gas phase for EuOH+, EuCl+, and TbO+ ions, which are produced by an electrospray ionization source and cooled to ~10 K in a cold, 22-pole ion trap. The UV photodissociation (UVPD) spectra of these ions show a number of sharp, well-resolved bands in the 30000–38000 cm–1 region, although a definite assignment of the spectra is difficult because of a high degree of congestion. We also measure an IR spectrum of the EuOH+ ion in the 3500–3800 cm–1 region by IR-UV double resonance spectroscopy, which reveals an OH stretching band at 3732 cm–1. We perform density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations of these ions in order to examine the nature of the transitions. The DFT results indicate that the states of highest spin multiplicity (octet for EuOH+ and EuCl+, and septet for TbO+) is substantially more stable than other states of lower spin multiplicity. The TD-DFT calculations suggest that the UV absorption of the EuOH+ and EuCl+ ions arises from Eu(4f)→Eu(5d, 6p) transitions, whereas the electronic transitions of the TbO+ ion are mainly due to the electron promotion of O(2p)→Tb(4f, 6s). The UVPD results of the lanthanide-containing ions in this study suggest the possibility of using lanthanide ions as “conformation reporters” for the gas-phase spectroscopy for large molecules.

lanthanide

ultraviolet spectroscopy

conformation

cold ion trap

Chemistry [ 430 ]

eng

American Chemical Society

Copyright (c) 2016 American Chemical Society

This document is the Accepted Manuscript version of a Published Work that appeared in final form in 'Inorganic Chemistry', copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.inorgchem.6b02134

This is not the published version. Please cite only the published version. この論文は出版社版でありません。引用の際には出版社版をご確認ご利用ください。

[ISSN] 0020-1669

[ISSN] 1520-510X

[DOI] 10.1021/acs.inorgchem.6b02134

[PMID] 27997155