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Updated: Aug 3, 2026

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
Four-component intergrowth structures of the metal-ion cage complexes
1School of Chemistry, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand.
Abstract:
The crystal structures of (1,5,9,13,20-pentamethyl-3,7,11,15,18,22-hexaazabicyclo[7.7.7]tricosane-kappa(6)N,N',N",N"',N"",N""')nickel(II) diperchlorate-x(water) (x = 0.530), [Ni(C(22)H(48)N(6))](ClO(4))(2).0.530H(2)O, and (1,5,9,13,20-pentamethyl-3,7,11,15,18,22-hexaazabicyclo[7.7.7]tricosane-kappa(6)N,N',N",N"',N"",N""')zinc(II) diperchlorate-x(water) (x = 0.608), [Zn(C(22)H(48)N(6))](ClO(4))(2).0.608H(2)O, are isomorphic and each is described as an intergrowth of four substructures, consistent with different modulations of an idealized parent structure of space group C2/c. Two substructures correspond to alternative orientations of a C1; structure for which x = 0 in the general formula [M(C(22)H(48)N(6))](ClO(4))(2).xH(2)O, and two substructures correspond to alternative origins of a P2(1)/n structure for which x = 1. Twinning also occurs. An analysis of the pseudosymmetry, a description of the refinement and a description of the refined structures are presented. The MN(6) coordination geometry is essentially octahedral, in contrast to the trigonal-prismatic geometry observed for the Cd(II) and Hg(II) complexes of the same ligand.
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