Acta Cryst. (2001). C57, 1308-1312 [doi:10.1107/S0108270101012112]
Abstract: Three flame retardants with very similar molecular structures showing three different packing patterns have been studied. The crystal structure of 2,2',6,6'-tetrachloro-4,4'-propane-2,2-diyldiphenol, C15H12Cl4O2, can be described as a packing of sheets. The packing shows a very short intermolecular Cl
Cl contact distance of 3.094 (2) Å between pairs of molecules inside each sheet. The crystal structure of 2,2',6-tribromo-4,4'-propane-2,2-diyldiphenol, C15H13Br3O2, can be described as a packing of doubly stranded helical square tubes. These square helices are interconnected through BrBr contacts between different helices. Finally, a previously known structure, 2,2',6,6'-tetrabromo-4,4'-propane-2,2-diyldiphenol [Simonov, Cheban, Rotaru & Bels'skii (1986). Kristallografiya, 31, 397-399], C15H12Br4O2, which is the most commonly used flame retardant and which has twofold rotational symmetry, has been refined in the correct absolute configuration. The structure shows large differences from the chloro analogue with regard to packing, van der Waals distances and hydrogen-bond distances.
Formula: C15H12Cl4O2, C15H13Br3O2 and C15H12Br4O2
Online 13 November 2001
 |   Structure factor file (CIF format) (136.2 kbytes) |
| Structure factor file (CIF format) (77.2 kbytes) |
| Structure factor file (CIF format) (80.3 kbytes) |
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