Premium
Timescale of π‐Stacking Formation in a Benzene Trimer Cation Formed by Ionization of the Parent Neutral Trimer: A Direct Ab Initio Molecular Dynamics Study
Author(s) -
TACHIKAWA Hiroto,
MIYAZAWA Yoshiyuki,
IURA Ryoshu
Publication year - 2018
Publication title -
chemistryselect
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.437
H-Index - 34
ISSN - 2365-6549
DOI - 10.1002/slct.201702663
Subject(s) - trimer , stacking , dimer , chemistry , ab initio , molecule , benzene , crystallography , ionization , computational chemistry , ab initio quantum chemistry methods , ion , organic chemistry
The π‐stacking interaction plays a crucial role in structural arrangements and molecular assemblies in several molecular systems. In the present study, π‐stacking formation in the benzene trimer cation, (Bz) 3 + , following ionization of the parent neutral benzene trimer, (Bz) 3 , was investigated using direct ab initio molecular dynamics to elucidate the timescale of π‐stacking formation and reaction mechanism in the ionized state. Cyclic (Bz) 3 was chosen as the benzene cluster. After ionizing (Bz) 3 , the structure drastically changed to a double π‐stacking form. The (Bz) 3 + product vibrated between two structural forms, (Bz‐Bz c ) + —Bz ↔ Bz—(Bz c ‐Bz) + , where Bz c is a benzene molecule located in the central position of (Bz) 3 + and (Bz c ‐Bz) + represents a dimer core composed of the benzene dimer cation. The timescale of π‐stacking formation was calculated as 300–380 fs. The absorption spectrum of (Bz) 3 + was blue‐shifted as a function of time. We discuss the reaction mechanism based on the theoretical results.