Locating conical intersections relevant to photochemical reactions

@article{Dick2008LocatingCI,
  title={Locating conical intersections relevant to photochemical reactions},
  author={Bernhard Dick and Yehuda Haas and Shmuel Zilberg},
  journal={Chemical Physics},
  year={2008},
  volume={347},
  pages={65-77}
}
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17 Citations

17 Citations

Citation Type

Citation Type

Systematic exploration of minimum energy conical intersection structures near the Franck-Condon region.
TLDR
The present approach combines the seam model function approach with the recently proposed single-component artificial force induced reaction method to find MECIs systematically, and requires neither a Hessian nor a derivative coupling vector.
Conical Intersections Leading to Chemical Reactions in the Gas and Liquid Phases
The current status of the role of conical intersections (CoIns) in molecular photochemistry is reviewed with a special emphasis on the procedures used to locate them. Due to space limitations, the…
Photoreactivity of a push-pull merocyanine in static electric fields: a three-state model of isomerization reactions involving conical intersections.
TLDR
It is shown that applying an external electric field or varying the solvent polarity changes the relative energies of the different transition states as well as that of the conical intersection, and thus different photochemical products can be obtained.
Description of Conical Intersections with Density Functional Methods.
TLDR
It is demonstrated that the commonly used linear-response time-dependent theory does not yield a proper description of conical intersections and the potential energy surfaces in their vicinity and that one should instead use alternative computational approaches.
Assessment of approximate computational methods for conical intersections and branching plane vectors in organic molecules.
TLDR
Comparisons support the use of the tested quantum-chemical methods for modeling the photochemistry of large organic and biological systems by demonstrating reasonable agreement in the computed relative energies.
In This Molecule There Must Be a Conical Intersection
Gradient Projection Method for Constraint Optimization and Relaxed Energy Paths on Conical Intersection Spaces and Potential Energy Surfaces.
  • B. Dick
  • Physics
    Journal of chemical theory and computation
  • 2009
TLDR
A gradient projection algorithm is presented that permits the application of several constraints during geometry optimization on electronic potential energy surfaces (PES) or conical intersection (CI) seams and determines relaxed energy paths (REP) without the need to assign an internal coordinate as the reaction coordinate.
Photoexcited conversion of gauche-1,3-butadiene to bicyclobutane via a conical intersection: energies and reduced density matrices from the anti-Hermitian contracted Schrödinger equation.
TLDR
The ACSE, MCSCF, and second-order multi-reference many-body perturbation theory (MRPT2) all demonstrate that there exists a family of pathways from gauche-1,3-butadiene to bicyclobutane via a conical intersection that are monotonically decreasing in energy, confirming a conjecture by Sicilia et al.
Theoretical investigation on the fast kinetics mechanism for vibronically activated photochromism in benzopyrans. The role of the conical intersection topology in driving the mode enhanced photoproducts
Automated Search for Minimum Energy Conical Intersection Geometries between the Lowest Two Singlet States S0/S1-MECIs by the Spin-Flip TDDFT Method.
TLDR
The present hybrid method of SMF/ADDF and SF-TDDFT is shown to be a promising approach to locate S0/S1-MECIs of large systems automatically with modest computational costs.
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References

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A 10×10 model Hamiltonian matrix for the 1A’ states of the H2Cl+ molecule in a valence‐bond basis is shown to exhibit conical intersections between states 2 and 3 along a line in configuration space…
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TLDR
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Optimization of Conical Intersections with Floating Occupation Semiempirical Configuration Interaction Wave Functions
We outline a new implementation of a minimal energy conical intersection (MECI) optimization algorithm within the context of semiempirical methods. Computationally, this semiempirical conical…
Locating Electronic Degeneracies of Polyatomic Molecules: A General Method for Nonsymmetric Molecules
A general method for finding all electronic degeneracies lying on the ground-state potential surface of a molecular system is proposed. The method is based on the idea that the spin pairing of the…
The role of conical intersections and excited state reaction paths in photochemical pericyclic reactions
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