Anharmonic Downward Distortion Following for Automated Exploration of Quantum Chemical Potential Energy Surfaces

Abstract

This article gives a comprehensive review of the anharmonic downward distortion following (ADDF) method. The ADDF method has been developed as an automated reaction path search method. This method follows the anharmonic downward distortion (ADD) toward transition states and dissociation channels starting from a local minimum on the potential energy surface (PES). Systematic applications of the ADDF method to all local minima provide a global network of reaction pathways on the PES of given chemical formulas. Various extensions have been proposed and applied to many interesting chemical problems such as elucidation of photodissociation mechanisms, structure prediction of Hbonded clusters, mechanistic studies of organometallic catalysis, design of generationconversion routes of amino acid molecules, and so on. It has also been employed in efficient construction of anharmonic PESs for highly accurate vibrational analysis. These developments and applications are illustrated with some representative results.

Analyses of bifurcation of reaction pathways on a global reaction route map: A case study of gold cluster Au5

“…Further details of the ADDF method are described in recent reviews. 5,6 Moreover, Maeda and Morokuma developed a new methodology to locate a TS geometry for A + B type reactions, named as artificial force induced reaction (AFIR), 7 which has made possible applications of GRRM more extensively. In 2014, the target of AFIR is extended to finding TSs of intramolecular reactions.…”

The effect of Mg2+ incorporation on the structure of calcium carbonate clusters: investigation by the anharmonic downward distortion following method

“…Thus, the large-ADD (l-ADD) technique is available for fast searches in ADDF, which is expected to explore the low energy structures along low barrier pathways 31 ; it has been successfully applied to various systems 27,28,31 and is applied also in the present study. The methods used to efficiently find maximal ADD directions in multi-dimensional potential-energy surfaces and the methods used to effectively choose l-ADDs from various ADDs have been described in previous papers [21][22][23][24]31 .…”

“…Therefore, in the present study, we use the anharmonic downward distortion following (ADDF) method [21][22][23][24] to make quantum chemical calculations intended to investigate the stable structure of Mg-containing calcium carbonate clusters. The ADDF method was recently developed to make an automated global exploration for reaction pathways on the quantum chemical potential energy surface (PES) of a given chemical formula possible without any assumptions of initial structures and reaction routes.…”

“…The ADDF method was recently developed to make an automated global exploration for reaction pathways on the quantum chemical potential energy surface (PES) of a given chemical formula possible without any assumptions of initial structures and reaction routes. In many cases, this method has been found to produce successful applications for the chemical reaction of molecules [24][25][26][27][28] . Furthermore, in such a case as this, where the structure of clusters is completely unknown, ADDF should be highly suitable in searching for stable configurations; however, it should be noted that there is no precedent for applying this technique to the early stages of crystal formation.…”

From nitrogen inversion in amines to stereoinversion in aminium salts: role of a single water molecule

“…Second, whereas the carbon-centered molecules are neutral, the nitrogen-centered molecules are positively charged, and therefore, there can be some considerable effect of the charge on the overall stereoinversion barriers. The stereochemical pathways in the present work are explored through a global reaction route-mapping (GRRM) [21,22] computational strategy discussed in the next section.…”