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Wiązanie wodorowe : wybrane zagadnienia

Sobczyk L.

Wiadomości Chemiczne

2001

[Z] 55, 7-8

593-627

In a short introduction the importance of hydrogen bonding is emphasized in life sciences and its role in molecular recognition and creation of living molecular systems. Then an attempt to define this specific molecular interaction is undertaken. Among most important features one should distinguish a particular repulsion potential which enables to approach directly interacting atoms on a distance markedly less than the sum of van der Waals radii. An important feature of hydrogen bonds is also the appearance of a double minimum potential for the proton motion. Among the main physical properties of hydrogen bonds there are analyzed dipole moments, nuclear magnetic resonance, quadrupole magnetic resonance, infra-red spectra and isotope effects. Most important isotope effects are related to infra-red spectra, geometry of bridges, phase transitions in hydrogen bonded ferroelectrics and fractionation factor. The evolution of the main characteristics is discussed depending on the acid-base properties expressed by means of the DpKa value of interacting components. A separate chapter is devoted to a dualistic nature of the interaction i.e. the structure creating and dynamical ones. The structure creating character is shown taking into account the induction of liquid crystalline properties while the dynamical properties are examplified on enzymic and photobiological processes and phase transitions in hydrogen bonded crystals. Current aspects of hydrogen bond interaction are limited to photoinduced proton transfer processes, the time resolved infra-red spectroscopy, low barrier hydrogen bonds (LBHB) and quantum molecular dynamics. In final remarks the importance of hydrogen bonding in searching for new materials of practical importance and crystal design are underlined.