The Mechanisms of Jahn-Teller Complex Reorientations

Yurii V. Yablokov,1 Maria A. Augustyniak-Jablokow,1 Michael Hitchman2 and Dirk Reinen3 

The temperature dependence of the magnetic complex conformation is known to be one of the distinguishable features of Jahn-Teller (JT) dynamics [1]. Keeping in mind electron paramagnetic resonance (EPR) as one of the most effective methods of studying the JT effect, we shall consider the problem of the transition from the low temperature, static JT situation to the high temperature, dynamic, motional averaged JT situation. The results of such processes are discussed in the literature [1-4]. At the same time, some important features - the nature of the transitions 

ADVANCES IN QUANTUM CHEMISTRY, VOLUME 44 ISSN 0065-3276 DOI 10.1016/S0065-3276(03)44031-8 

X- and Q-band EPR in the temperature range 4.2-300 K were used to obtain data for the Cu(H20)g+ JT complex. The cases of the JT complexes in a site of cubic (or trigonal) symmetry (a), tetragonal elongated symmetry (b), and tetragonal compressed symmetry (c) are analyzed. The crystallo-hydrates are suitable and convenient objects for investigation, as representatives of this class of compounds  

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