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}
}
17 Citations
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.
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.
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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