title: Revisiting Vibrational Circular Dichroism Spectra of (S)-(+)-Carvone and (1S,2R,5S)-(+)-Menthol Using SimIR/VCD Method.
abstract: The VCD spectra of (S)-(+)-carvone and (1S,2R,5S)-(+)-menthol are recalculated using the DFT method with extended conformation and configuration spaces. The calculated individual and averaged spectra are compared against observed ones using the previously reported similarity index, SV. It is found that the SV population forms approximately two normal distributions, depending on whether a spectrum matches the observed one or not. This statistical character can be used to estimate the error in absolute configuration (AC) assessments. To avoid erroneous AC assignments and incomplete conformation searching, it is advisible to employ a minimum |SV| of 0.2 and maximize it using conformation averaging. It is demonstrated that this approach is suitable and robust for flexible chiral molecules.
authors.affiliation: Sanofi US, 1041 Route 202-206, Bridgewater, New Jersey 08807, United States.
authors.forename: Jian
authors.initials: J
authors.lastname: Shen
authors.affiliation: Sanofi US, 1041 Route 202-206, Bridgewater, New Jersey 08807, United States.
authors.forename: Yi
authors.initials: Y
authors.lastname: Li
authors.affiliation: Sanofi US, 1041 Route 202-206, Bridgewater, New Jersey 08807, United States.
authors.forename: Roy
authors.initials: R
authors.lastname: Vaz
authors.affiliation: National Institute of Advanced Industrial Science and Technology, AIST Tsukuba West, 16-1 Onogawa, Tsukuba, Ibaraki 305-8569, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Izumi