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Updated: Aug 7, 2026

Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing
Published on: March 22, 2019
Infrared multiphoton spectra from metal dication complexes in the gas phase
Guohua Wu1, Jingang Guan, Georgina D C Aitken
1Department of Physical Chemistry, School of Chemistry, The University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
Abstract:
Infrared multiphoton spectra have been recorded for the first time from metal dication complexes held in an ion trap. The photofragmentation of [M(pyridine)4]2+ complexes has been observed in the range 920-1090 cm(-1) and for M=Cu2+, Mg2+ and Zn2+. The narrow absorption features are identified as vibrational modes of the pyridine molecule and comparisons with calculations suggest that the Mg2+ and Zn2+ ion complexes have D2d (compressed tetrahedron) structures, and that the Cu2+ complex is probably square-planar (D4h).
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