• structural order;
  • Raman scattering cross section;
  • liquid-core optical fiber


Using the technique of liquid-core optical fiber (LCOF), we measured the Raman scattering cross sections (RSCSs) of the carbon–carbon (C[BOND]C) stretching vibrational modes of all-trans-β-carotene in carbon disulfide (CS2) at concentrations ranging from 10−6 to 10−11M. It was found that the RSCSs of all-trans-β-carotene were extremely high with decreasing concentration, and the absolute RSCS of C stretching modes of all-trans-β-carotene reached the value of 2.6 × 10−20 cm2 molecule−1 Sr−1 at 8 × 10−11M, which is larger than at 8 × 10−6 Mby 4 orders of magnitude. A theoretical interpretation of the anomalous experimental results is given, which introduces a qualitative nonlinear model of coherent weakly damped electron-lattice vibrations in structural order of all-trans-β-carotene. Copyright © 2010 John Wiley & Sons, Ltd.