The Importance of Large-Amplitude Motions for the Interpretation of Mid-Infrared Vibrational Absorption and Circular Dichroism Spectra: 6,6′-Dibromo-[1,1′-binaphthalene]-2,2′-diol in Dimethyl Sulfoxide

• Published in: The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory Molecules, spectroscopy, kinetics, environment, & general theory, 2014-07, Vol.118 (26), p.4766-4777
• Main Authors: Heshmat, Mojgan, Baerends, Evert Jan, Polavarapu, Prasad L, Nicu, Valentin Paul
• Format: Article
• Language: English
• Subjects: Bromine - chemistry; Circular Dichroism - methods; Circularity; Dichroism; Dimethyl sulfoxide; Dimethyl Sulfoxide - chemistry; Models, Molecular; Molecular Dynamics Simulation; Molecular Structure; Naphthacenes - chemistry; Naphthalenes - chemistry; Orientation; Perturbation methods; Physical chemistry; Solvents; Spectra; Spectrophotometry, Infrared; Water - chemistry
• ISSN: 1089-5639; 1520-5215
• DOI: 10.1021/jp4114738

Using the 6,6′-dibromo-[1,1′-binaphthalene]-2,2′-diol molecule and its vibrational absorption (VA) and vibrational circular dichroism (VCD) spectra measured in deuterated dimethyl sulfoxide as example, we present a first detailed study of the effects induced in VCD spectra by the large-amplitude motions of solvent molecules loosely bound to a solute molecule. We show that this type of perturbation can induce significant effects in the VA and VCD spectra. We also outline a computational procedure that can effectively model the effects induced in the spectra and at the same time provide detailed structural information regarding the relative orientations of moieties involved in a solute–solvent molecular complex.