Angol
The book reviews the results of vibration-rotational spectroscopy of molecules obained recently by combining modern computational methods of quantum chemistry with the new techniques of high-resolution rotational and vibration-rotational spectroscopy. It shows for example that the tunnelling vibration-rotational spectroscopy of the van der Waals complexes provides a new look at intermolecular forces which the high precision and sensitivity of the submillimetre-wave and Fourier transform microwave spectroscopy make it possible to study complex rotational spectra of molecules in excited vibrational states. New results of high level "ab initio" quantum chemical computations of vibrational and rotational energy levels and dipole moment functions of unusual molecules will be discussed together with the recent discovery of clustering of energy levels in asymmetric tops. Group theoretical analysis of floppy molecules, especially the tunnelling effects in nongrid molecules, will also be discussed.
