Related Experiment Video
Updated: May 1, 2026

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
1D to 3D heterobimetallic complexes tuned by cyanide precursors: synthesis, crystal structures, and magnetic
Daopeng Zhang1, Weijiang Si, Ping Wang
1College of Chemical Engineering, Shandong University of Technology , Zibo 255049, China.
Abstract:
Five new heterobimetallic complexes, namely, {[Ni(L)][Fe(bpb)(CN)2]}ClO4 (L = 2,12-dimethyl-3,7,11,17-tetraazabicyclo[11.3.1]heptadeca-1(17),13,15-triene, bpb(2-) = 1,2-bis(pyridine-2-carboxamido)benzenate) (1), {[Ni(L)]3[M(CN)6]2}·7H2O (M = Fe (2), Cr (3)), {[Ni(L)]2[Mo(CN)8]}·CH3CN·13H2O (4), and {[Ni(L)]2[W(CN)8]}·16H2O (5), were assembled from the polyaza macrocycle nickel(II) compound and five cyanidometalate precursors containing different numbers of cyanide groups. Single-crystal X-ray diffraction analysis reveals their different structure ranging from a cyanide-bridged cationic polymeric single chain for 1, a two-dimensional network for 2 and 3, and a three-dimensional network for 4 and 5. In addition, a systematic investigation over the magnetic properties of 1-3 indicates the ferromagnetic magnetic coupling between neighboring Fe(III)/Cr(III) and Ni(II) ions through the bridging cyanide group. For complex 1, the magnetic susceptibility has been simulated by the Seiden model using the Hamiltonian H = -J∑i=0(N)SiSi+1, leading to the magnetic coupling constant of J = 3.67 cm(-1). The two-dimensional magnetic complexes exhibit three-dimensional magnetic ordering behavior with a magnetic phase transition temperature of TC = 4.0 K for 2 and TN = 6.0 K for 3, respectively.
Related Concept Videos
Valence Bond Theory
Colors and Magnetism
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
Metal-Ligand Bonds
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
Structural Isomerism
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly,...
Coordination Number and Geometry
Formation of Complex Ions

