A. Katrusiak
Apr 1, 1993
Citations
0
Influential Citations
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Citations
Journal
Solid State Communications
Abstract
Abstract An order-disorder phase transition has been observed in the crystals of 2-methyl-1,3-cyclohexanedione at 244(1)K by a DTA and X-ray powder diffraction method. The phase transition is induced by the onset of ordering of methylene groups C(4)H 2 and C(5)H 2 in the molecular ring, differently than in the crystals of 1,3-cyclohexanedione where only one methylene group C(5)H 2 is disordered. Large-amplitude intramolecular vibrations of the methylene groups in the cyclohexene ring in simple cyclic β-diketoalkanes can be activated in various modes, depending on the conformational properties of the molecular ring, on the tensor of inertia of the molecules, or on their strongest intermolecular interactions.