Vibrational Spectroscopy and Structural Phase Transitions in Molecular Crystals
نویسنده
چکیده
Vibrational spectroscopy can give useful informa tian, both structural and dynamical, about phase transitions in molecular crystals. In particular, the data concerning the mechanism of the transformation at molecular level can be obtained. This is illustrated by examples of pure van der Waals crystals such as 3,5-dichloropyridine and 4-methylpyridine, hydrogen bonded malonic acid, inorganic ferroelectrics cesium dihydrogen phosphate and triammonium hydrogen disulphate, a superionic protonic eonductor cesium hydrogen sulphate and a coordination compound: propylene diammonium manganese tetrachloride.
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