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We report infrared photodissociation spectra of manganese-CO2 cluster anions, [Mn(CO2)n]- (n = 2-10) to probe structural motifs characterizing the interaction between Mn and CO2 in the presence of an excess electron. We interpret the experimental spectra through comparison with infrared spectra predicted from density functional theory calculations. The cluster anions consist of core ions combining a Mn atom with a variety of ligands, solvated by additional CO2 molecules. Structural motifs of ligands evolve with increasing cluster size from simple monodentate and bidentate CO2 ligands to oxalate ligands and combinations of these structural themes. [ABSTRACT FROM AUTHOR]

Es wurde untersucht, wie sich die reduktive Aktivierung von CO2 durch einen atomaren Bi ‐ Modellkatalysator unter aprotischer Solvatisierung verändert. Infrarot ‐ Photodissoziationsspektroskopie massenselektierter [Bi(CO2)n]− ‐ Clusterionen wurde genutzt, um die Strukturveränderung der molekularen ionischen Kerne dieser Cluster bei wachsender Clustergröße zu verfolgen. Die Interpretation der Infrarotspektren erfolgte durch Vergleich mit Ergebnissen auf der Basis von Dichtefunktionaltheorie. Die Resultate zeigen, dass CO2 mit Bi in Gegenwart eines Zusatzelektrons ein Metalloformiat ‐ Ion (BiCOO−) bildet. Solvatisierung durch zusätzliche CO2 ‐ Moleküle führt zur Stabilisierung eines BiI ‐ Oxalat ‐ Komplexes und damit zur Änderung des Kernions. Solvatisierung macht den Unterschied: Zunehmende Clustergröße in [Bi(CO2)n]− ‐ Clusteranionen bewirkt eine Strukturänderung des molekularen ionischen Kerns (siehe Bild; schwarz C, rot O, blau Metall). Dieses Verhalten liefert wichtige Rückschlüsse zum Verständnis der molekularen Mechanismen bei der heterogenen elektrochemischen CO2 ‐ Reduktionskatalyse unter aprotischen Bedingungen. [ABSTRACT FROM AUTHOR]

In this work, we investigated how the reductive activation of CO2 with an atomic bismuth model catalyst changes under aprotic solvation. IR photodissociation spectroscopy of mass-selected [Bi(CO2) n]− cluster ions was used to follow the structural evolution of the core ion with increasing cluster size. We interpreted the IR spectra by comparison with density-functional-theory calculations. The results show that CO2 binds to a bismuth atom in the presence of an excess electron to form a metalloformate ion, BiCOO−. Solvation with additional CO2 molecules leads to the stabilization of a bismuth(I) oxalate complex and results in a core ion switch. [ABSTRACT FROM AUTHOR]

The mid-infrared spectral region is of great technical and scientific interest because most molecules display fundamental vibrational absorptions in this region, leaving distinctive spectral fingerprints. To date, the limitations of mid-infrared light sources such as thermal emitters, low-power laser diodes, quantum cascade lasers and synchrotron radiation have precluded mid-infrared applications where the spatial coherence, broad bandwidth, high brightness and portability of a supercontinuum laser are all required. Here, we demonstrate experimentally that launching intense ultra-short pulses with a central wavelength of either 4.5??m or 6.3??m into short pieces of ultra-high numerical-aperture step-index chalcogenide glass optical fibre generates a mid-infrared supercontinuum spanning 1.5??m to 11.7??m and 1.4??m to 13.3??m, respectively. This is the first experimental demonstration to truly reveal the potential of fibres to emit across the mid-infrared molecular 'fingerprint region', which is of key importance for applications such as early cancer diagnostics, gas sensing and food quality control. [ABSTRACT FROM AUTHOR]

We report infrared photodissociation spectra of manganese-CO 2 cluster anions, [Mn(CO 2 ) n ] - (n = 2-10) to probe structural motifs characterizing the interaction between Mn and CO 2 in the presence of an excess electron. We interpret the experimental spectra through comparison with infrared spectra predicted from density functional theory calculations. The cluster anions consist of core ions combining a Mn atom with a variety of ligands, solvated by additional CO 2 molecules. Structural motifs of ligands evolve with increasing cluster size from simple monodentate and bidentate CO 2 ligands to oxalate ligands and combinations of these structural themes.

In this work, we investigated how the reductive activation of CO 2 with an atomic bismuth model catalyst changes under aprotic solvation. IR photodissociation spectroscopy of mass-selected [Bi(CO 2 ) n ] - cluster ions was used to follow the structural evolution of the core ion with increasing cluster size. We interpreted the IR spectra by comparison with density-functional-theory calculations. The results show that CO 2 binds to a bismuth atom in the presence of an excess electron to form a metalloformate ion, BiCOO - . Solvation with additional CO 2 molecules leads to the stabilization of a bismuth(I) oxalate complex and results in a core ion switch., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)