title: Automated Search for Minimum Energy Conical Intersection Geometries between the Lowest Two Singlet States S0/S1-MECIs by the Spin-Flip TDDFT Method.
abstract: Automated search for minimum energy conical intersection geometries between the lowest two singlet states (S0/S1-MECIs) was performed by combining the anharmonic downward distortion following (ADDF) method, the seam model function (SMF) approach, and the spin-flip (SF) TDDFT method. SMF/ADDF has been employed previously in automated searches for MECIs on potential energy surfaces (PESs) with expensive multireference methods. In this work, we adopt the SF-TDDFT method that enables efficient optimization of S0/S1-MECIs in the framework of TDDFT. To evaluate the performance of the present approach, it was applied to ethylene and 1,3-butadiene. The present method automatically gave unknown S0/S1-MECIs as well as all previously reported ones. Therefore, 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.
authors.affiliation: Department of Chemistry, Faculty of Science, Hokkaido University , Sapporo 060-0810, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Harabuchi
authors.affiliation: Department of Chemistry, Faculty of Science, Hokkaido University , Sapporo 060-0810, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Maeda
authors.affiliation: Department of Chemistry, Faculty of Science, Hokkaido University , Sapporo 060-0810, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Taketsugu
authors.affiliation: Fukui Institute for Fundamental Chemistry, Kyoto University , 34-4 Takano Nishihiraki-cho, Sakyo, Kyoto 606-8103, Japan.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Minezawa
authors.affiliation: Fukui Institute for Fundamental Chemistry, Kyoto University , 34-4 Takano Nishihiraki-cho, Sakyo, Kyoto 606-8103, Japan.|Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University , Atlanta, Georgia 30322, United States.
authors.forename: Keiji
authors.initials: K
authors.lastname: Morokuma