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Updated: Jun 8, 2026

Method to Measure Tone of Axial and Proximal Muscle
Published on: December 14, 2011
Rotational strength sign and normal modes description: A theoretical and experimental comparative study in bicyclic
Francisco Partal Ureña1, Juan Ramón Avilés Moreno, Juan Jesús López González
1Department of Physical and Analytical Chemistry, University of Jaén, Jaén, Spain. fpartal@ujaen.es
Abstract:
A comparative study of the Vibrational circular dichroism (VCD) patterns in three bicyclic terpenes with related molecular structures, (+)-(R)-α-pinene, (-)-(S)-β-pinene, and (-)-(S)-verbenone, is carried out. The study is done in the light of normal mode descriptions from a previous vibrational analysis. Although normal modes corresponding to identical molecular moieties shown the same description, rotational strength does not follow the Cahn-Ingold-Prelog descriptor-related sign in some cases, i.e., they do not present opposite signs depending on stereochemical description of the molecule.
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