Circular dichroism simulations of chiral buckybowls by means curvature analyses

Abstract

A detailed understanding and interpretation of chiral properties of molecular systems, especially in condensed phase, often requires computational models that allow their structural and electronic features to be connected to the observed experimental spectra. The present paper is focused on modelling the circular dichroism spectra of chiral buckybowls, combining topological aspects and the density functional theory. For the first time Ball Pivoting Algorithm was proposed to hook up the chemical topology to the DFT through the surface reconstruction. Particularly, the gaussian curvature of a constructed probe set of corannulene and sumanene derivatives was used as discriminant parameter to benchmark a list of 10 functionals (B3LYP, B97D, M06-2X, HSEH1PBE, wB97XD, CAM-B3LYP, LC-wPBE, TPSSTPSS, mPW1PW91 and APFD). The latter provide to be noticeably accurate to reproduce the curvature effect of the considered molecules. A TD-DFT/BOMD mixed approach provided a comprehensive overview of the spectral chiral pattern prediction trends when multiple DFT functionals are scanned. The preliminary topological analysis efforts were then recompensed with the very precise computed CD spectra, again APFD confirmed as the leader functional, this time for TD-DFT vertical transition calculations. Therefore, we strongly recommend the use of the of dispersion embedded APFD functional coupled with the 6–311++G(2d,2p) basis set for the computation of the functionalized chiral buckybowls ECD spectra.© 2017 Elsevier Inc. All rights reserved.