title: Supramolecular structure in s-block metal complexes of sulfonated monoazo dyes: discrepant packing and bonding behavior of ortho-sulfonated azo dyes.
abstract: The first solid-state structures of ortho-sulfonated monoazo dyestuffs are reported and compared to those of their para- and meta-sulfonated analogues. The structures of the 16 Na, K, Cs, Mg, Ca, Sr, and Ba ortho-sulfonated salts are found to have fewer M-O(3)S bonds than their isomeric equivalents and this in turn means that the metal type is no longer the prime indicator of which structural type will be adopted. M-O(3)S bonds are replaced by M-OH(2), M-HOR and M-pi interactions, apparently for steric reasons. As well as new bonding motifs, the changed dye shape also leads to new packing motifs. The simple organic/inorganic layering ubiquitous to the para- and meta-sulfonated dye salt structures is replaced by variations (organic bilayers, inorganic channels), each of which correlates with a different degree of molecular planarity in the sulfonated azo dye anion.
authors: WestCHEM, Department of Pure & Applied Chemistry, University of Strathclyde, Glasgow G1 1XL, UK. a.r.kennedy@strath.ac.uk
authors: Alan R
authors: AR
authors: Kennedy
authors: Prokopis C
authors: PC
authors: Andrikopoulos
authors: Jean-Baptiste
authors: JB
authors: Arlin
authors: David R
authors: DR
authors: Armstrong
authors: Neil
authors: N
authors: Duxbury
authors: David V
authors: DV
authors: Graham
authors: Jennifer B A
authors: JB
authors: Kirkhouse