Acta Crystallographica Section C

Crystal Structure Communications

Volume 57, Part 5 (May 2001)

organic compounds

 

Pseudosymmetry and phase transition in dimethyl 2,3-bis(tricyclo[3.3.1.1^3,7]dec-2-ylidene)butanedioate

J. W. Bats, M. A. Grundl and A. S. K. Hashmi

Abstract: The crystal structure of the title compound, C₂₆H₃₄O₄, shows a reversible phase transition at about 178 K. The structure of the high-temperature phase contains two independent molecules related by pseudosymmetry elements. Cooling through the phase-transition temperature results in a doubling of the c axis. The low-temperature structure contains four independent molecules related by pseudosymmetry elements. The phase transition results in a rearrangement of some weak intermolecular C-HO interactions. The number of very weak C-HO interactions, with HO distances between 2.8 and 2.9 Å, is increased in the low-temperature structure.

Formula: C₂₆H₃₄O₄

	Structure factor file (CIF format) (589.8 kbytes) Contains datablock I_at_204K
	Structure factor file (CIF format) (1280.2 kbytes) Contains datablock I_at_142K

To open or display or play some files, you may need to set your browser up to use the appropriate software. See the full list of file types for an explanation of the different file types and their related mime types and, where available links to sites from where the appropriate software may be obtained.

The download button will force most browsers to prompt for a file name to store the data on your hard disk.

Where possible, images are represented by thumbnails.

Copyright © International Union of Crystallography
IUCr Webmaster