title: Efficient Two-Step Procedures for Locating Transition States of Surface Reactions.
abstract: Using various two-step strategies, we examined how to accurately locate transition states (TS) of reactions using the example of eight reactions at metal surfaces with 14-33 moving atoms. These procedures combined four path-finding methods for locating approximate TS structures (nudged elastic band, standard string, climbing image string, and searching string, using a conjugate gradient or a modified steepest-descent method for optimization and two types of coordinate systems) with subsequent local refinement by two dimer methods. The dimer-Lanczos variant designed for this study required on average 20% fewer gradient calls than the standard dimer method. During the path finding phase, using mixed instead of Cartesian coordinates reduced the numbers of gradient calls on average by an additional 21%, while using a modified steepest-descent method improved that key efficiency criterion on average by 13%. For problematic cases we suggest strategies especially adapted to the problem at hand.
authors.affiliation: Department Chemie and Catalysis Research Center, Technische Universität München, 85747 Garching, Germany.
authors.forename: Astrid
authors.initials: A
authors.lastname: Nikodem
authors.affiliation: Department Chemie and Catalysis Research Center, Technische Universität München, 85747 Garching, Germany.
authors.forename: Alexei V
authors.initials: AV
authors.lastname: Matveev
authors.affiliation: Department Chemie and Catalysis Research Center, Technische Universität München, 85747 Garching, Germany.|Department of Chemistry and Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China.
authors.forename: Bo-Xiao
authors.initials: BX
authors.lastname: Zheng
authors.affiliation: Department Chemie and Catalysis Research Center, Technische Universität München, 85747 Garching, Germany.|Institute of High Performance Computing, 1 Fusionopolis Way, #16-16 Connexis, Singapore 138632, Singapore.
authors.forename: Notker
authors.initials: N
authors.lastname: Rösch