Acta Crystallographica Section B

Structural Science

Volume 58, Part 1 (February 2002)

research papers

Acta Cryst. (2002). B58, 125-133 [ doi:10.1107/S0108768101017955 ]

Coupling of the lactone-ring conformation with crystal symmetry in 6-hydroxy-4,4,5,7,8-pentamethyl-3,4-dihydrocoumarin

A. Budzianowski and A. Katrusiak

Abstract: Conformational disorder and inversions of the lactone ring induce structural transformations in the crystals of 6-hydroxy-4,4,5,7,8-pentamethyl-3,4-dihydrocoumarin, C₁₄H₁₈O₃. The onset of ordering of the lactone ring at 300 K proceeds continuously, changes the space group from P2₁/m to P2₁/c and doubles the unit cell; the abrupt inversion of the lactone rings at 225 K changes the crystal translational symmetry in the (010) plane. The mechanism combining the molecular conformation and dynamics with the crystal structure, its symmetry, and phase transitions is presented.

Keywords: coumarin; lactone-ring conformation; order-disorder; phase transition.


	Structure factor file (CIF format) (41.6 kbytes) Contains datablock a308

	Structure factor file (CIF format) (38.8 kbytes) Contains datablock a319

	Structure factor file (CIF format) (35.8 kbytes) Contains datablock a329

	Structure factor file (CIF format) (165.2 kbytes) Contains datablock cum110c

	Structure factor file (CIF format) (169.6 kbytes) Contains datablock cum150c

	Structure factor file (CIF format) (120.1 kbytes) Contains datablock cum220

	Structure factor file (CIF format) (151.5 kbytes) Contains datablock cum222

	Structure factor file (CIF format) (120.3 kbytes) Contains datablock cum224

	Structure factor file (CIF format) (132.3 kbytes) Supplementary material

	Structure factor file (CIF format) (131.2 kbytes) Supplementary material

	Structure factor file (CIF format) (130.7 kbytes) Supplementary material

	Structure factor file (CIF format) (130.1 kbytes) Supplementary material

	Structure factor file (CIF format) (133.5 kbytes) Supplementary material

	Structure factor file (CIF format) (91.5 kbytes) Supplementary material

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