STRUCTURE AND STABILITY OF MOLECULAR AND IONIC COMPLEXES OF AlCl3 WITH PYRAZINE AND 4,4'-BIPYRIDYL
E. I. Davydova1, A. Yu. Timoshkin1, G. Frenking2
1St. Petersburg State University, St. Petersburg, Russia
2Philipps-Universität Marburg, Marburg, Germany
Keywords: quantum chemical calculations, molecular complexes, ionic complexes, aluminum chloride, pyrazine, 4,4'-bipyridyl, structure, stability
Abstract
Structural and thermodynamic characteristics of molecular and ionic complexes of aluminum trichloride with pyrazine (pyz) and 4,4'-bipyridyl (bipy) are calculated at the RI-BP86/def2-SVP level. It is found that for molecular 2AlCl3·3L and 4AlCl3·3L complexes an energy difference between isomers does not exceed 4 kJ/mol, and the rotation barrier of the AlCl3 moiety relative to the N–Al–N bond does not exceed 24 kJ/mol. A comparison of the stability of molecular and ionic complexes of aluminum in the gas phase shows that the maximum energy difference is ~60 kJ/mol. For L = pyz the molecular complex is more stable whereas for L = bipy it is the ionic one.
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