Most of the research in contemporary physical chemistry is devoted to the development of methods that extend our understanding, interpretation, and capacity to predict structural properties and dynamic behavior of molecules. The optical and magnetic spectroscopies, as well as diffraction techniques, are the principal methods for studying properties of molecules, biomolecules, and biopolymers of which the vast majority are chiral. On the other hand, information on molecular configuration can be obtained mainly from optical spectroscopies because other well-established spectroscopic techniques used for structural investigations, such as crystallographic, ESR, and NMR methods, do not allow for registration of signals from an individual conformer owing to intrinsic slow response to structural changes. This is the reason why the optical spectroscopy methods, based on natural chiroptical phenomena, have become so important and their renaissance in the last decade is noticed. Vibrational circular dichroism (VCD) spectroscopy is one such chiroptical technique that sheds new light on many important phenomena studied intensively. We provide an overview of recent theoretical predictions and innovative VCD observations of chirality transfer (called by other authors "induced chirality") from a chiral molecule to an achiral one as a result of hydrogen bond interactions between them. In this tutorial review we search for answers as to whether we can obtain further information about intermolecular interactions using the VCD technique. In our opinion this technique has opened new horizons for both understanding and monitoring intermolecular interactions and it could be used as a relatively new and powerful physicochemical method.

For the first time the argon-matrix low-temperature IR spectra of cysteine are recorded. They reveal a quite complicated spectral pattern, which can also be reproduced in the N2 matrix. Assignment of the observed spectra is undertaken on the basis of comparison of the experimental and calculated B3LYP/aug-cc-pVDZ anharmonic IR spectra. The presence of at least three, and possibly even six or more, cysteine conformers with and without intramolecular hydrogen bonding is confirmed. On the basis of the calculated vibrational circular dichroism spectra, we predict this technique to be more distinctive for conformers than IR absorption is.

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This paper presents a discussion of the interaction energies, conformations, vibrational absorption (VA, harmonic and anharmonic) and vibrational circular dichroism (VCD) spectra for conformers of monomeric chiral d(-)-lactic acid and their complexes with water at the DFT(B3LYP)/aug-cc-pVDZ and DFT(B3LYP)/aug-cc-pVTZ levels. A detailed analysis has been performed principally for the two most stable complexes with water, differing by lactic acid conformation. The VCD spectra were found to be sensitive to conformational changes of both free and complexed molecules, and to be especially useful for discriminating between different chiral forms of intermolecular hydrogen bonding complexes. In particular, we show that the VCD modes of an achiral water molecule after complex formation acquire significant rotational strengths whose signs change in line with the geometry of the complex. Using the theoretical prediction, we demonstrate that the VCD technique can be used as a powerful tool for structural investigation of intermolecular interactions of chiral molecules and can yield information complementary to data obtained through other molecular spectroscopy methods.

For the first time the argon-matrix low-temperature FTIR spectra of beta-alanine are recorded. They reveal a quite complicated spectral pattern which suggests the presence of several beta-alanine conformers in the matrix. To interpret the spectra, the eighteen beta-alanine conformers, stable in the gas phase, are estimated at the B3LYP and MP2 levels combined with the aug-cc-pVDZ. Ten low-energy structures are reoptimized at the QCISD/aug-cc-pVDZ and B3LYP and MP2 levels by using the aug-cc-pVTZ basis sets. Assignment of the experimental spectra is undertaken on the basis of the calculated B3LYP/aug-cc-pVDZ anharmonic IR frequencies as well as careful estimation of the conformer population. The presence of at least three beta-alanine conformers is demonstrated. The detailed analysis of IR spectra points to the possible presence of five additional beta-alanine conformers.