A combined experimental and theoretical investigation of photodissociation dynamics of IBr(-) and IBr(-)(CO(2)) on the B ((2)Σ(1/2)(+)) excited electronic state is presented. Time-resolved photoelectron spectroscopy reveals that in bare IBr(-) prompt dissociation forms exclusively I∗ + Br(-). Compared to earlier dissociation studies of IBr(-) excited to the A' ((2)Π(1∕2)) state, the signal rise is delayed by 200 ± 20 fs. In the case of IBr(-)(CO(2)), the product distribution shows the existence of a second major (∼40%) dissociation pathway, Br∗ + I(-). In contrast to the primary product channel, the signal rise associated with this pathway shows only a 50 ± 20 fs delay. The altered product branching ratio indicates that the presence of one solvent-like CO(2) molecule dramatically affects the electronic structure of the dissociating IBr(-). We explore the origins of this phenomenon with classical trajectories, quantum wave packet studies, and MR-SO-CISD calculations of the six lowest-energy electronic states of IBr(-) and 36 lowest-energy states of IBr. We find that the CO(2) molecule provides sufficient solvation energy to bring the initially excited state close in energy to a lower-lying state. The splitting between these states and the time at which the crossing takes place depend on the location of the solvating CO(2) molecule.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1063/1.3584203 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Molecular Uranium Dioxide-Mediated CO Photoreduction.
J Am Chem Soc
January 2025
Department of Chemistry and Engineering Research Center of Advanced Rare-Earth Materials of Ministry of Education, Tsinghua University, Beijing 100084, China.
The reduction of CO mediated by transition metals has garnered significant interest, yet little is known about the reduction of CO using f-element compounds. Herein, the reduction of CO to CO by tetravalent uranium (U) compound UO is investigated via matrix isolation infrared spectroscopy and quantum chemical study. Our results reveal that a stable carbonate intermediate OUCO () can be prepared at low temperatures (4-12 K).
View Article and Find Full Text PDFTransformation of Distinct Superatoms to Superalkalis by Successive Ligation of Thymine Nucleobases.
J Phys Chem A
January 2025
Fujian Key Laboratory of Drug Target Discovery and Structural and Functional Research, Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, The School of Pharmacy, Fujian Medical University, Fuzhou, Fujian 350108, People's Republic of China.
The ligation strategy has been widely used in the chemical synthesis of atomically precise clusters. A series of thymine (T)-ligated Al-T ( = Be, Al, C; = 1-5) complexes have been studied to reveal the effect of DNA nucleobase ligands on the electronic structures of different superatoms in the present work. In addition to its protective role, the successive attachment of thymine ligands significantly lowers the adiabatic ionization energies (AIEs) of the studied Al superatoms with filled and unfilled electronic shells.
View Article and Find Full Text PDFNoble-Metal-Free ZnII-Anchored Pyrene-Based Covalent Organic Framework (COF) for Photocatalytic Fixation of CO2 from Dilute Gas into Bioactive 2-Oxazolidinones.
ChemSusChem
January 2025
Indian Institute of Technology Ropar, Chemistry, Nangal Road, 140001, Rupnagar, INDIA.
Photocatalytic conversion of CO2 into value-added chemicals offers a propitious alternative to traditional thermal methods, contributing to environmental remediation and energy sustainability. In this respect, covalent organic frameworks (COFs), are crystalline porous materials showcasing remarkable efficacy in CO2 fixation facilitated by visible light owing to their excellent photochemical properties. Herein, we employed Lewis acidic Zn(II) anchored pyrene-based COF (Zn(II)@Pybp-COF) to facilitate the photocatalytic CO2 utilization and transformation to 2-oxazolidinones.
View Article and Find Full Text PDFThe Role of Surfactant in Electrocatalytic Carbon Dioxide Reduction in the Absence of Metal Cations.
ACS Electrochem
January 2025
Stephenson Institute for Renewable Energy (SIRE) and the Department of Chemistry, University of Liverpool, Liverpool L69 7ZF, United Kingdom.
Carbon dioxide electroreduction does not occur on Au when metal cations are absent from the electrode surfaces. Here we show that the electroreduction can be enabled without metal cations, albeit with low efficiency, by the presence of cationic surfactants on Au. The findings demonstrate that in addition to possibly stabilizing CO reduction intermediates the presence of surfactants plays a role in suppressing the competing reactions.
View Article and Find Full Text PDFContinuous Electrochemical Carbon Capture via Redox-Mediated pH Swing─Experimental Performance and Process Modeling.
J Phys Chem Lett
January 2025
Department of Process Engineering and Technology of Polymer and Carbon Materials, Wroclaw University of Science and Technology, Wyb. St. Wyspiańskiego 27, 50-370 Wrocław, Poland.
We investigate a continuous electrochemical pH-swing method to capture CO from a gas phase. The electrochemical cell consists of a single cation-exchange membrane (CEM) and a recirculation of a mixture of salt and phenazine-based redox-active molecules. In the absorption compartment, this solution is saturated by CO from a mixed gas phase at high pH.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!