It is well recognized that the measurements of optical rotatory dispersion of proteins with strong absorption bands are extremely difficult because of the diminishing intensity of the emergent light. Until very recently, these studies were made possible only by improving the light source and also frequently by a wide opening of the slit width on the monochromator at the expense of spectral puri...

Interpretation of the Raman optical activity (ROA) of peptides is difficult because of molecular flexibility and interaction with the solvent. Typically, simulations and experiments are compared in terms of a qualitative agreement between the spectra. However, on a series of the Pro-Gly, Gly-Pro, Pro-Ala, and Ala-Pro dipeptides more precise conformer ratios could be obtained with the aid of the...

To shed light on intramolecular charge-transfer phenomena in 1,2,3-triazole-linked materials, a series of 1,2,3-triazole-linked push-pull chromophores were prepared and studied experimentally and computationally. Investigated modifications include variation of donor and/or acceptor strength and linker moiety as well as regioisomers. Photophysical characterization of intramolecular charge-transf...

This review covers conformational and configurational assignments in natural product molecules using chiroptical spectroscopy reported over the last 15 years. Special attention is given to vibrational optical activity methods associated with quantum mechanical calculations.

We report the first observation of Raman optical activity (ROA) by coherent anti-Stokes Raman scattering. Thanks to the more freedom of polarization configurations in coherent anti-Stokes Raman scattering than in spontaneous Raman spectroscopy, the contrast ratio of the chiral signal to the achiral background has been improved markedly. For (-)-β-pinene, it is 2 orders of magnitude better than ...

Discovered in 1813, the conoscopic interference pattern observed due to light propagating through a crystal, kept between crossed polarizers, shows isochromates and isogyres, respectively containing information about the dynamic and geometric phase acquired by the beam. We propose and demonstrate a closed-fringe Fourier analysis method to disentangle the isogyres from the isochromates, leading ...

The toroidal dipole is a localized electromagnetic excitation, distinct from the magnetic and electric dipoles. While the electric dipole can be understood as a pair of opposite charges and the magnetic dipole as a current loop, the toroidal dipole corresponds to currents flowing on the surface of a torus. Toroidal dipoles provide physically significant contributions to the basic characteristic...

In this paper a combination of a rotation invariant method with a method which utilizes rotation normalization is proposed. Both methods used are based on 2D/3D Krawtchouk moments. The first method is an extension of that which was originally introduced in [1] and utilizes 2D Krawtchouk moments while the second method was originally introduced in [2] and utilizes 3D Krawtchouk moments.1

Crystal specimens of the γ-polymorph of achiral glycine which crystallize in space groups P31 and P32 as determined by the anomalous X-ray scattering method are shown to be laevorotatory and dextrorotatory, respectively, as determined by optical rotation of the crystals.