Premium
Low‐energy structures of benzene clusters with a novel accurate potential surface
Author(s) -
Bartolomei M.,
Pirani F.,
Marques J. M. C.
Publication year - 2015
Publication title -
journal of computational chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.907
H-Index - 188
eISSN - 1096-987X
pISSN - 0192-8651
DOI - 10.1002/jcc.24201
Subject(s) - ab initio , potential energy surface , chemistry , benzene , ab initio quantum chemistry methods , computational chemistry , potential energy , molecule , cluster (spacecraft) , interaction energy , chemical physics , molecular physics , atomic physics , physics , computer science , organic chemistry , programming language
The benzene‐benzene (Bz‐Bz) interaction is present in several chemical systems and it is known to be crucial in understanding the specificity of important biological phenomena. In this work, we propose a novel Bz‐Bz analytical potential energy surface which is fine‐tuned on accurate ab initio calculations in order to improve its reliability. Once the Bz‐Bz interaction is modeled, an analytical function for the energy of theBz nclusters may be obtained by summing up over all pair potentials. We apply an evolutionary algorithm (EA) to discover the lowest‐energy structures ofBz nclusters (for n = 2 − 25 ), and the results are compared with previous global optimization studies where different potential functions were employed. Besides the global minimum, the EA also gives the structures of other low‐lying isomers ranked by the corresponding energy. Additional ab initio calculations are carried out for the low‐lying isomers ofBz 3andBz 4clusters, and the global minimum is confirmed as the most stable structure for both sizes. Finally, a detailed analysis of the low‐energy isomers of the n = 13 and 19 magic‐number clusters is performed. The two lowest‐energyBz 13isomers show S 6 and C 3 symmetry, respectively, which is compatible with the experimental results available in the literature. TheBz 19structures reported here are all non‐symmetric, showing two central Bz molecules surrounded by 12 nearest‐neighbor monomers in the case of the five lowest‐energy structures. © 2015 Wiley Periodicals, Inc.