Acta Crystallographica Section B

Structural Science

Volume 68, Part 1 (February 2012)

research papers

Acta Cryst. (2012). B68, 57-65    [ doi:10.1107/S0108768111051159 ]

Face-to-face stacking of quinoid rings of alkali salts of bromanilic acid

K. Molcanov and B. Kojic-Prodic

Abstract: A series of alkali salts of hydrogen bromanilic acid trihydrates (K+, Rb+ and Cs+, potassium, rubidium and caesium 2,5-dibromo-4-hydroxy-3,6-dioxocyclohexa-1,4-dien-1-olate trihydrate), bromanilic acid tetrahydrate (Na+, disodium 2,5-dibromo-3,6-dioxocyclohexa-1,4-diene-1,4-diolate tetrahydrate) and bromanilic acid dihydrates (K+, Rb+ and Cs+, dipotasium, dirubidium and dicaesium 2,5-dibromo-3,6-dioxo­cyclohexa-1,4-diene-1,4-diolate dihydrate) were prepared and studied by single-crystal X-ray diffraction. Their crystal packings are dominated by quinoid ring stacking. The monoanionic quinoid rings pack face-to-face without offset and with short centroid separations (3.25-3.30 Å), while the dianionic rings form offset stacks (1.4-1.8 Å) with a larger centroid separation (3.8-4.1 Å).

Keywords: bromanilic acid; [pi]-stacking; quinoid rings; electron delocalization; X-ray structure; pseudosymmetry.

pdfdisplay filedownload file

Portable Document Format (PDF) file
[ doi:10.1107/S0108768111051159/gp5046sup8.pdf ]
Extra figures and tables


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.

 bibliographic record in  format

  Find reference:   Volume   Page   
  Search:     From   to      Advanced search

Copyright © International Union of Crystallography
IUCr Webmaster