title: Influence of the counteranion on the formation of polymeric networks by metal complexes of hexamethylenebis(acetamide).
abstract: An investigation into the anion dependence of the network-forming ability of metal complexes of hexamethylenebis(acetamide), CH3CONH(CH2)6NHCOCH3 (HMBA), has resulted in the X-ray characterization of the compounds [Co(HMBA)3][Co(NCS)4], 1, [Nd(HMBA)3][Nd(NO3)6].2CHCl3, 2, [Co(HMBA)3][HgCl4], 3, and [Mn(HMBA)3][HgBr4].3CHCl3, 4. The structures of compounds 1, 3, and 4 each comprise cationic frameworks formed by the bridging action of HMBA ligands binding octahedrally to the cobalt or manganese centers and, in the cases of 3 and 4, the formation of tetrahedral HgX4(2-) anions by transfer of the respective halide ions from Co or Mn to Hg. Complete anion (NO3-) transfer between Nd centers is also a key factor in the structure of 2, which forms a cationic 3-D network of HMBA-bridged octahedrally coordinated Nd centers with occluded [Nd(NO3)6]3- anions. These types of inter-metal-anion transfer, with consequent complex counteranion formation, appear to facilitate the network-forming ability of the metal-HMBA cationic arrays.
authors.affiliation: Department of Chemistry, Imperial College of Science, Technology and Medicine, London SW7 2AY, U.K.
authors.forename: N P
authors.initials: NP
authors.lastname: Chatterton
authors.forename: D M
authors.initials: DM
authors.lastname: Goodgame
authors.forename: D A
authors.initials: DA
authors.lastname: Grachvogel
authors.forename: I
authors.initials: I
authors.lastname: Hussain
authors.forename: A J
authors.initials: AJ
authors.lastname: White
authors.forename: D J
authors.initials: DJ
authors.lastname: Williams