Quantum dynamics study of fulvene double bond photoisomerization: The role of intramolecular vibrational energy redistribution and excitation energy

Blancafort, Lluı́s; Gatti, Fabien; Meyer, Hans‐Dieter

doi:10.1063/1.3643767

Cited by 27 publications

(33 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The FC‐CI tor MEP in Figure B shows that the BLA distortion rapidly decreases at the beginning of the path, while the torsion θ about the exocyclic C‐C bond picks up somewhat later along the MEP and reaches torsional angle of 64.3°. The optimized FC‐CI tor MEP is generally consistent with the shape of the S 0 and S 1 PESs evaluated on the basis of the CASSCF calculations . The CI tor occurs at 76.3 kcal/mol with respect to the S 0 FC energy and is 11.7 kcal/mol lower than CI plan .…”

Section: Resultssupporting

confidence: 90%

Next‐generation quantum theory of atoms in molecules for the ground and excited states of fulvene

Huang

Momen

Azizi

et al. 2018

Int J of Quantum Chemistry

View full text Add to dashboard Cite

A vector‐based representation of the chemical bond is introduced, which we refer to as the bond‐path framework set B = {p, q, r}, where p, q, and r represent 3 eigenvector‐following paths with corresponding lengths H*, H, and the familiar quantum theory of atoms in molecules (QTAIM) bond‐path length (BPL). The intended application of B is for molecules subjected to various types of reactions and distortions, including photoisomerization reactions, applied torsions θ, or normal modes of vibration. The lengths H* and H of the eigenvector‐following paths are constructed using the e 1 and e 2 Hessian eigenvectors, respectively, along the bond path, these corresponding to the least and most preferred directions of charge density accumulation. In particular, the paths p and q provide a vector representation of the scalar QTAIM ellipticity ε. The bond‐path framework set B is applied to the excited state deactivation of fulvene that involves distortions along various intramolecular degrees of freedom, such as the bond stretching/compression of bond‐length alternation and bond torsion distortions. We find that the H* and H lengths can differentiate between the ground and excited electronic states, in contrast to the QTAIM BPL. Five unique paths were presented for B = {(p0,p1), (q0,q1), r} for the ground and first excited states where the profile of the scaling factor, the ellipticity ε, reveals a large unexpected asymmetry for the excited state.

show abstract

Section: Resultssupporting

confidence: 90%

Next‐generation quantum theory of atoms in molecules for the ground and excited states of fulvene

Huang

Momen

Azizi

et al. 2018

Int J of Quantum Chemistry

View full text Add to dashboard Cite

show abstract

“…However, in light of the recent advances, there is also a case to be made for reopening the old debate -can mechanistic insights into the energy flow dynamics lead to better control strategies? It is not entirely unreasonable to expect that a subtle interplay between the IVR dynamics and the controlling field must occur in many of the quantum control studies [25,26]. Hence, is it possible to envisage situations wherein IVR might actually aid, rather than thwart, the control process?…”

Section: Introductionmentioning

confidence: 99%

Driven coupled Morse oscillators: visualizing the phase space and characterizing the transport

Sethi

Keshavamurthy

2012

Molecular Physics

View full text Add to dashboard Cite

Recent experimental and theoretical studies indicate that intramolecular energy redistribution (IVR) is nonstatistical on intermediate timescales even in fairly large molecules. Therefore, it is interesting to revisit the the old topic of IVR versus quantum control and one expects that a classicalquantum perspective is appropriate to gain valuable insights into the issue. However, understanding classical phase space transport in driven systems is a prerequisite for such a correspondence based approach and is a challenging task for systems with more then two degrees of freedom. In this work we undertake a detailed study of the classical dynamics of a minimal model system -two kinetically coupled coupled Morse oscillators in the presence of a monochromatic laser field. Using the technique of wavelet transforms a representation of the high dimensional phase space, the resonance network or Arnold web, is constructed and analysed. The key structures in phase space which regulate the dissociation dynamics are identified. Furthermore, we show that the web is nonuniform with the classical dynamics exhibiting extensive stickiness, resulting in anomalous transport. Our work also shows that pairwise irrational barriers might be crucial even in higher dimensional systems.

show abstract

“…As our case study problem, we followed and characterize the evolution of the charge density accompanying the rotation of the fulvene exo‐double bond. This problem was chosen because of its quintessential orbital character—the reduction of bond order accompanying the breaking of a π‐bond—and because it has been well studied yet remains relevant because of the biradical or zwitterionic character of the rotated state. Thus, it is our hope that this example might serve as a problem that allows us to focus on the charge density decomposition and characterization while remaining topical.…”

Section: Introductionmentioning

confidence: 99%

Charge density analysis attending bond torsion: A bond bundle case study

Goss

Wilson

Morgenstern

et al. 2018

Int J of Quantum Chemistry

View full text Add to dashboard Cite

For nearly a century chemical understanding has been tied to the properties of bonds, although more often than not, these bond properties are rooted in molecular orbital or valence bond representations of the electronic structure. Technological advances, however, are allowing for experimental measurements of the density via high resolution X-ray diffraction, while theoretical insights are opening the door to its direct calculation using fast and potentially versatile orbital free DFT methods. Capitalizing on these emerging tools without sacrificing orbital derived understanding has spurred a search for density based representations that deliver the same information available from the orbital perspective. We show that recent extensions of the QTAIM formalism are useful as a means of recovering some of the bond properties that have become an intrinsic part of our chemical understanding. Specifically, we compute from the density the changing bond order and bond order distribution accompanying the rotation about a double bond using the well-studied fulvene molecule as a test case. We compare the picture that emerges from this density based perspective with that stemming from molecular orbital approaches and argue that the two viewpoints are compatible. K E Y W O R D S bond bundle, bond torsion, electron charge density, fulvene, quantum theory of atoms and molecules 1 | INTRODUCTION The modern view of chemical phenomena is inextricably intertwined with the orbital representation of electron movement and redistribution.Roald Hoffman has argued [1] that the orbital perspective holds a special place in chemistry because of the qualitative framework it provides for understanding. Alas, many of the more advanced and accurate methods do not easily lend themselves to orbital representations; for example: band approaches, many electron methods, orbital free approaches, and particularly the direct experimental measurement of electron density. [2] The chemistry community is thus confronted with a conundrum: How will we build on the hard-won understanding based on orbital concepts as we exploit advances in computational and experimental chemistry?Here, we show that by exploiting the quantum theory of atoms in molecules (QTAIM) [3] and its recent extensions [4][5][6][7][8] it is possible to decompose the electronic charge density into regions called bond-bundles that may be described by conventional orbital parameters. As our case study problem, we followed and characterize the evolution of the charge density accompanying the rotation of the fulvene exo-double bond. This problem was chosen because of its quintessential orbital character-the reduction of bond order accompanying the breaking of a π-bond-and because it has been well studied [9][10][11][12][13][14] yet remains relevant because of the biradical or zwitterionic character of the rotated state. Thus, it is our hope that this example might serve as a problem that allows us to focus on the charge density decomposition and characterization while remaining topical.Although w...

show abstract

Quantum dynamics study of fulvene double bond photoisomerization: The role of intramolecular vibrational energy redistribution and excitation energy

Cited by 27 publications

References 40 publications

Next‐generation quantum theory of atoms in molecules for the ground and excited states of fulvene

Next‐generation quantum theory of atoms in molecules for the ground and excited states of fulvene

Driven coupled Morse oscillators: visualizing the phase space and characterizing the transport

Charge density analysis attending bond torsion: A bond bundle case study

Contact Info

Product

Resources

About