University of Sussex
Browse

File(s) not publicly available

Ultraviolet Photofragmentation Spectroscopy of Alkaline Earth Dication Complexes with Pyridine and 4-Picoline (4-Methyl pyridine)

journal contribution
posted on 2023-06-08, 05:34 authored by Hamish Stewart, Guohua Wu, Lifu Ma, Michael Barclay, Andreia Dias Vieira, Andrew King, Hazel CoxHazel Cox, Anthony J Stace
A detailed experimental and theoretical study has been undertaken of the UV photofragmentation spectroscopy of the alkaline earth metal dications Mg2+, Ca2+, and Sr2+ complexed with pyridine and 4-methyl pyridine (4-picoline). The ion complexes have been prepared using the pick-up technique and held in an ion trap where their internal temperature has been reduced to <150 K. Exposure of the trapped ions to tunable UV laser radiation leads to the appearance of photofragments with intensities that show significant variation as a function of wavelength. For all three metal dications, the resultant spectra show evidence of resolved features. Time-dependent density functional theory (TDDFT) has been used to identify possible electronic transitions that might be present in the [M(pyridine)4]2+ complexes (M = Mg, Ca, and Sr) within the wavelength range studied. These calculations show that the spectra are dominated by strong p* ? p and weaker p* ? n transitions localized on the pyridine ligands. The calculations correctly identify those regions of the experimental spectra where UV transitions begin to occur in the complexes and also the wavelengths at which absorption maxima are reached; however, more subtle features of the spectra are difficult to assign with confidence.

History

Publication status

  • Published

Journal

Journal of Physical Chemistry A

ISSN

1089-5639

Publisher

American Chemical Society

Issue

25

Volume

115

Page range

6948-6960

Department affiliated with

  • Chemistry Publications

Notes

I was the lead computational/theoretical author, my co-main author is experimental.

Full text available

  • No

Peer reviewed?

  • Yes

Legacy Posted Date

2012-02-06

Usage metrics

    University of Sussex (Publications)

    Categories

    No categories selected

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC