Dataset Information

Photochemical activation of carbon dioxide in Mg+(CO2)(H2O)0,1.

ABSTRACT: We combine multi-reference ab initio calculations with UV-VIS action spectroscopy to study photochemical activation of CO2 on a singly charged magnesium ion, [MgCO2(H2O)0,1]+, as a model system for the metal/ligand interactions relevant in CO2 photochemistry. For the non-hydrated species, two separated Mg+ 3s-3p bands are observed within 5.0 eV. The low-energy band splits upon hydration with one water molecule. [Mg(CO2)]+ decomposes highly state-selectively, predominantly via multiphoton processes. Within the low-energy band, CO2 is exclusively lost within the excited state manifold. For the high-energy band, an additional pathway becomes accessible: the CO2 ligand is activated via a charge transfer, with photochemistry taking place on the CO2 - moiety eventually leading to a loss of CO after absorption of a second photon. Upon hydration, already excitation into the first and second excited state leads to CO2 activation in the excited state minimum; however, CO2 predominantly evaporates upon fluorescence or absorption of another photon.

SUBMITTER: Pascher TF

PROVIDER: S-EPMC7335376 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Photochemical activation of carbon dioxide in Mg+(CO2)(H2O)0,1.

Pascher Tobias F TF Barwa Erik E van der Linde Christian C Beyer Martin K MK Ončák Milan M

Theoretical chemistry accounts 20200704 8

We combine multi-reference ab initio calculations with UV-VIS action spectroscopy to study photochemical activation of CO2 on a singly charged magnesium ion, [MgCO2(H2O)0,1]+, as a model system for the metal/ligand interactions relevant in CO2 photochemistry. For the non-hydrated species, two separated Mg+ 3s-3p bands are observed within 5.0 eV. The low-energy band splits upon hydration with one water mole ...[more]

PMID: 32655309

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Dataset Information

Photochemical activation of carbon dioxide in Mg+(CO2)(H2O)0,1.

Publications

Photochemical activation of carbon dioxide in Mg<sup>+</sup>(CO<sub>2</sub>)(H<sub>2</sub>O)<sub>0,1</sub>.

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