In the title copper(II) complex, the metal atom is coordinated by two N atoms and two O atoms from two bidentate (E)-1-[(2,4,6-tri­bromo­phen­yl)diazen­yl]naphthalen-2-ol ligands, forming a slightly distorted square-planar environment. In the isotypic nickel(II) and palladium(II) complexes, the metal atoms are located on centres of inversion, hence the metal coordination spheres have perfect square-planar geometries.

In the title complex, [Pd(C17H13N2O2)Cl], the PdIIatom is tetracoordinated by an N and two O atoms of an (E)-1-[(2-methoxyphenyl)diazenyl]naphthalen-2-olate ligand and by a Cl atom, and has a square-planar coordination. In the crystal, molecules are linked by pairs of C—H...Cl hydrogen bonds, forming inversion dimers. The dimers are linkedviaoffset π–π interactions [intercentroid distance = 3.546 (3) Å], forming chains running parallel to [100].

The title complex, [Cu(C17H13N2O2)2], crystallizes with two independent mol­ecules in the asymmetric unit. Each CuII atom has a distorted ocahedral coordination environment defined by two N atoms and four O atoms from two tridentate 1-[(E)-(2-meth­oxy­phen­yl)diazen­yl]naphthalen-2-olate ligands. In the crystal, the two mol­ecules are linked via weak C—H⋯O hydrogen bonds which in turn stack parallel to [010]. A region of disordered electron density, most probably disordered methanol solvent molecules, was corrected for using the SQUEEZE routine in PLATON [Spek (2015). Acta Cryst. C71, 9–18]. Their formula mass and unit-cell characteristics were not taken into account during refinement.

The title compound, [Ag2(CN)3(C9H8N2)2], is a mixed-valence disilver mol­ecular complex. The Ag+ ion has the expected linear coordination geometry, while the Ag2+ centre is six-coordinated with a distorted [AgN5C] octa­hedral geometry. This compound belongs to class 1 or class 2 complexes in the Robin–Day classification.