AI Article Synopsis
- Gaussian wavepacket methods are gaining traction in studying nonadiabatic molecular dynamics, particularly in the context of phenol's photodissociation.
- A new efficient algorithm named Direct Dynamics variational Multi-Configurational Gaussian (DD-vMCG) is employed for full-dimensional quantum dynamic calculations that examine six electronic states involved in this process.
- The findings reveal that including the fifth singlet excited state notably influences the nonadiabatic photodissociation of phenol, confirming rapid relaxation mechanisms through specific conical intersections.
Article Abstract
Gaussian wavepacket methods are becoming popular for the investigation of nonadiabatic molecular dynamics. In the present work, a recently developed efficient algorithm for the Direct Dynamics variational Multi-Configurational Gaussian (DD-vMCG) method has been used to describe the multidimensional photodissociation dynamics of phenol including all degrees of freedom. Full-dimensional quantum dynamic calculations including for the first time six electronic states (ππ, 1ππ*, 1πσ*, 2πσ*, 2ππ*, 3ππ*), along with a comparison to an existing analytical 4-state model for the potential energy surfaces are presented. Including the fifth singlet excited state is shown to have a significant effect on the nonadiabatic photodissociation of phenol to the phenoxyl radical and hydrogen atom. State population and flux analysis from the DD-vMCG simulations of phenol provided further insights into the decay mechanism, confirming the idea of rapid relaxation to the ground state through the ππ/1πσ* conical intersection.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1039/d1cp01843d | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Enantioselective Complexation of Protonated Tyrosine by a Chiral Crown-ether: The Nature of the Hydrogen Bonds Makes the Difference.
Chemphyschem
November 2024
International Research Frontiers Initiative (IRFI), Institute of Innovative Research, Institute of Science Tokyo, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Japan.
Article Synopsis
- The study examines the complexes formed between 18-crown-6-tetracarboxylic acid (18C6TA) and the two enantiomers of protonated tyrosine (L- and D-Tyr) using mass spectrometry, laser spectroscopy, and DFT calculations in a cryogenic ion trap.
- Spectra reveal multiple isomers for each complex, with some isomers capable of interconverting under IR irradiation, while conformer-selective vibrational spectroscopy shows all structures featuring an internally hydrogen-bonded folded arrangement of the crown ether.
- Complexes with L-Tyr display two NH…O interactions with the ether's oxygen and additional hydrogen bonds, while D-Tyr complexes are more flexible,
Nondirect-Product Local Diabatic Representation with Smolyak Sparse Grids.
J Chem Theory Comput
November 2024
Institute of Natural Sciences, Westlake Institute for Advanced Study, Hangzhou 310024, China.
Modeling nonadiabatic conical intersection dynamics is critical for understanding a wide range of photophysical, photochemical, and biological phenomena. Here we develop a nonadiabatic conical intersection wave packet dynamic method in the local diabatic representation using Smolyak sparse grids. Employing sparse grids avoids the direct-product grids in configuration space and alleviates the exponential scaling of computation costs with the molecular size.
View Article and Find Full Text PDFObservation of the Infrared-Induced Structural Change in the Microscopic Hydrogen Bond Network of Phenol-Methanol Cluster Cations in a Cold-Ion Trap.
J Phys Chem A
July 2024
Department of Chemistry, School of Science, Kitasato University, Sagamihara 252-0373, Japan.
To gain insight into microscopic hydrogen bond networks, we measured ultraviolet photodissociation (UVPD) spectra of the phenol-methanol 1:3 cluster cation, [PhOH(MeOH)] trapped in a variable temperature ion trap. At low temperatures, an isomer with a ring-type hydrogen bond structure dominates, whereas at higher temperatures the chain-type isomers become dominant due to the flexibility of their hydrogen bond structures. We also found a clear temperature dependence of the spectral features, such as band position and width.
View Article and Find Full Text PDFPhotodissociation dynamics of m- and p-cresol in the S1 state: Interplay between the mode-randomization and H atom tunneling reaction.
J Chem Phys
November 2023
Department of Chemistry, KAIST, Daejeon 34141, Republic of Korea.
The H atom tunneling dissociation dynamics of the S1 state of meta- or para-cresol has been investigated by using the picosecond time-resolved pump-probe spectroscopy in a state-specific manner. The S1 state lifetime (mainly due to the H atom tunneling reaction) is found to be mode-dependent whereas it quickly converges and remains constant as the rapid intramolecular vibrational energy redistribution (IVR) starts to participate in the S1 state relaxation with the increase of the S1 internal energy (Eint). The IVR rate and its change with increasing Eint have been reflected in the parent ion transients taken by tuning the total energy (hνpump + hνprobe) just above the adiabatic ionization threshold (so that the dissipation of the initial mode-character could be monitored as a function of the reaction time), indicating that the mode randomization rate into the S1 isoenergetic manifolds exceeds the tunneling rate quite early in terms of Eint for m-cresol (≤∼1200 cm-1) or p-cresol (≤∼800 cm-1) compared to the case of phenol (≤∼1800 cm-1).
View Article and Find Full Text PDFMicrohydration of the adamantane cation: intracluster proton transfer to solvent in [Ad(HO)] for ≥ 3.
Phys Chem Chem Phys
May 2023
Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstr. 36, 10623 Berlin, Germany.
Radical cations of diamondoids are important intermediates in their functionalization reactions in polar solvents. To explore the role of the solvent at the molecular level, we characterize herein microhydrated radical cation clusters of the parent molecule of the diamondoid family, adamantane (CH, Ad), by infrared photodissociation (IRPD) spectroscopy of mass-selected [Ad(HO)] clusters. IRPD spectra of the cation ground electronic state recorded in the CH/OH stretch and fingerprint ranges reveal the first steps of this fundamental H-substitution reaction at the molecular level.
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!