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Ab Initio Study of the Magneto‐Optical Rotation of Diastereoisomers
Author(s) -
Kula Mathias,
Cappelli Chiara,
Coriani Sonia,
Rizzo Antonio
Publication year - 2008
Publication title -
chemphyschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.016
H-Index - 140
eISSN - 1439-7641
pISSN - 1439-4235
DOI - 10.1002/cphc.200700650
Subject(s) - faraday effect , optical rotation , chemistry , diastereomer , enantiomer , dipole , tartaric acid , ab initio , density functional theory , specific rotation , ab initio quantum chemistry methods , crystallography , computational chemistry , molecular physics , stereochemistry , magnetic field , molecule , physics , quantum mechanics , organic chemistry , citric acid
Experimental studies on the natural optical activity and Faraday rotation of the three different stereoisomers of tartaric acid were reported recently by Ruchon et al. [ Chem. Phys. Lett . 2005 , 412 , 411]. The authors noted that the Faraday rotation of the meso ( R,S ) system differed from those of the ( S,S ) and ( R,R ) enantiomers, and derived a simple dipole–dipole interaction model to describe what they claim to be a “new property”. We present the results of both density functional theory (DFT) and coupled cluster calculations for a structurally elementary model system composed of two chiral carbon atoms presenting three diastereoisomers (C 2 H 2 Cl 2 F 2 ), as well as a detailed DFT study of the natural and magnetic‐field‐induced optical rotation of tartaric acid. The effects of electron correlation, basis set, and conformational flexibility are analyzed. It is found that the specific Faraday rotations of the chiral ( R,R ) and meso forms of tartaric acid (for λ =632.8 nm) differ by about 3 %, a value which is quite close in magnitude—but of opposite sign—to that obtained with the simplified model proposed by Ruchon and co‐workers.