Why does the disorder of R-pn and rac-pn ligands in the quasi-one-dimensional bromo-bridged NiIII complexes, [Ni(pn)2Br]Br2 (pn=1,2-diaminopropane) afford similar STM patterns?

The disordered patterns of R- and rac-1,2-diaminopropane (pn) in quasi-one-dimensional bromo-bridged Ni(III) complexes, [NiIII(pn)2Br]Br2, have been investigated by single-crystal X-ray structure determination and scanning tunneling microscopy (STM). X-ray structure determination shows that the methyl moieties are disordered on the right- and left-hand sides with half occupancies in both compounds, while the carbon atoms of the ethylene moieties of pn ligands are disordered in [Ni(rac-pn)2Br]Br2 and not disordered in [Ni(R-pn)2Br]Br2. In the STM images of both compounds, the bright spots are not straight but fluctuated with the similar patterns. We have concluded that tunnel current from the STM tip to metal ions are detected via methyl groups of pn ligands.     

Electronic structure of Co(III) doped bromo-bridged Ni complexes, [Ni1-xCox(chxn)2Br]Br2

This article describes the electronic structure of the Co(III) doped Br bridged Ni(III) complexes, [Ni(1-x)Cox(chxn)2Br]Br2 (x = 0.01, 0.02, 0.05, and 0.11) by using a optical spectroscopy, scanning tunneling microscopy (STM), and electron spin resonance spectroscopy. In the optical reflectivity spectrum, the new band was formed at about 0.5 eV, which is reasonably recognized as the d(z2) band of doped Co(III) ions. In the STM images of [Ni(1-x)Cox(chxn)2Br]Br2, the bright spots attributable to the tunnel current from the Fermi level of the STM tip to the conduction band of the sample were observed. In addition, some brighter spots were also observed. Because the number of the brighter spots is in good agreement with that of doped Co species, the brighter spots can be assigned to doped Co(III) sites. These are reasonably explained by the tunnel current from the Fermi level of the tip to the d(z2) band of Co(III). The Curie spin concentration was gradually increased with increasing Co(III) ions, which is explained by the scissions of the S = 1/2 1D antiferromagnetic chains.     

Tuning of electronic structures of quasi-one-dimensional bromo-bridged Ni(III) complexes with strong electron-correlation by doping of Co(III) ions, [Ni(1-x)Co(x)(Chxn)(2)Br]Br(2)

We have succeeded in synthesizing the Ni(III) complexes doped by Co(III) ions, [Ni(1-x)Co(x)(chxn)(2)Br]Br(2) (x = 0, 0.043, 0.093, and 0.118) by using an electrochemical oxidation method. The single-crystal reflectance spectrum of x = 0.118 shows an intense CT band about 0.5 eV, which is lower than that of [Ni(chxn)(2)Br]Br(2) (1.3 eV). The single-crystal electrical conductivities at room temperature of these compounds increase with increase of the amounts of doping of Co(III) ions. In the ESR spectra, peak-to-peak line widths DeltaH(pp) at room temperature change about 600 G in [Ni(chxn)(2)Br]Br(2) to 200 G in x = 0.118. Such a large x dependence of DeltaH(pp) seems to be ascribed to the increasing contribution from the increasing Curie spins which have smaller line width. Therefore, we have tuned the electronic structures of quasi-one-dimensional bromo-bridged Ni(III) complexes with strong electron correlations by doping of Co(III) ions.     

In situ time-resolved XAFS study of the reaction mechanism of bromobenzene homocoupling mediated by [Ni(cod)(bpy)

A homocoupling reaction mechanism of bromobenzene mediated by the [Ni(cod)(bpy)] (cod = 1,5-cyclooctadiene; bpy = 2,2'-bipyridine) complex was investigated by means of in situ time-resolved X-ray absorption fine structure (XAFS) and factor analysis. A dimer intermediate [Ni(bpy)(Ph)Br](2) proposed in the previous studies by other groups is too dilute to observe with the XAFS technique; however, the structures and concentrations on the time course of a reactant [Ni(cod)(bpy)], an intermediate [Ni(bpy)(Ph)Br(dmf)(2)], and a byproduct [Ni(bpy)Br(2)(dmf)] during reaction are revealed by this combination.     

Adsorptive behavior of dimethylglyoxime on Au(111)

Dimethylglyoxime (DMG) adsorbed on Au(111) was investigated using electrochemical scanning tunneling microscopy (STM) and X-ray photoelectron spectroscopy (XPS). STM experiments revealed three different structures of adsorbed DMG at open circuit potential (~0.07 V versus Ag/AgCl): (2√3×2√3)R30°-α, (2√3×4√3)R30°-β, and (2√3×4√3)R30°-γ. The coverage of adsorbed DMG obtained using XPS was 0.33. A combination of structural and quantitative information identified the adsorbed DMG as an anionic tetramer, held together by intermolecular hydrogen bonding and arrayed in three ordered patterns. Domains of adsorbed DMG underwent phase transitions between the observed structures, most likely due to the influence of the STM tip. However, a significant correlation between the observed structures and the imaging conditions was not found. The ordered layers existed only at open circuit potential as evidenced by their disappearance when the potential was shifted to 0.2 or -0.15 V. The ordered layers were also removed by immersion in a solution of Ni(2+), implying that the adsorbed DMG was converted to a soluble dimer complex with the Ni(2+) ion. This particular observation is discussed in terms of the rigidity of the organic network.     

Pressure-dependent Ni-O phase transitions and Ni oxide formation on Pt(111): an in situ STM study at elevated temperatures

Growth, atomic structure and O2 partial pressure dependent phase transitions of Ni-O structures and thin NiO films on Pt(111) have been studied using scanning tunnelling microscopy (STM), low-energy electron diffraction (LEED), and Auger electron spectroscopy (AES). In situ STM experiments were performed during film growth by reactive metal deposition at elevated temperatures (400-550 K) and variable O2 pressure. Depending on the substrate temperature, one-dimensional network-like Ni-O structures and islands with (7x1) and (4x2) reconstructions are formed during the initial stages of growth. These structures transform reversibly to a (2x2) reconstruction in a narrow O2 pressure range of 1.5-2x10(-6) mbar and can be monitored by in situ STM. Upon reduction of the O2 pressure to <10(-10) mbar pseudomorphic Ni monolayers are obtained. The defect-free ordering of Ni atoms on Pt(111) in a single stacking domain indicates an O-surfactant induced growth mode. The structural properties of the O2 pressure-dependent Ni-O phases are discussed in a simple model assuming NiO(001)-like atomic arrangements in the adsorbate overlayer. At higher coverage stable (111)-oriented NiO islands grow in a three-dimensional mode.     

Synthesis and characterization of 1-Methyl-4-mercaptopiperidine complexes of nickel(II), palladium(II) and platinum(II)

Summary Complexes of formulae Ni(HRS)₂X₂ (X=Cl or Br), M(HRS)₂Y₂ (M=Ni or Pd; Y=NO₂ or C1O₄), Pd(HRS)X₂ (X=Cl, Br or I), Pt(HRS)X₂ (X=Cl or Br), Pt(HRS)₂(ClO₄)₂ and M(RS)₂ (M=Pd or Pt) where HRS and RS denote 1-methyl-4-mercaptopiperidine in the zwitterionic or in the thiolato form, respectively, have been prepared and characterized. In all the complexes the ligands are coordinated exclusively through sulphur. Polymeric structures consisting of square-planar geometry with sulphur-bridged metal atoms are proposed in each case.     

The Assembly and Molecular Structure of a Novel One-dimensionalCyanide-bridged [Ni(pn)_2Ni(CN)_4]_n·nH_2 O Complex

IntroductionSincetheearlyworkofPedersen',CramZandLehn',molecularassemblyhasattractedmuchattentionfromscientistsofdifferentareas,rangingfromchemistrytosolid-statephysicsandbiology,becauseofthepotentialimpactonmaterialscience,catalysisandmetallo-biochemistry#.ThepreparationandstUdyofpolynuclear,cyanide-bridgedmetalcomplexeshaveattractedconsiderableinterestoverthepastdecades-I3.Cyanide-bridgedpolynuclearcomplexesaresuitablefortheconstructionofsuchdevicestoobtainmoleculescapableofestablishingspe…     

Co-ordination compounds of diacetyldihydrazone and diacetylbis(monomethylhydrazone)

Summary Diacetyldihydrazone (DADH) forms only six-coordinate complexes with iron(II), cobalt(II), nickel(II) and zinc(II). In M(DADH)₂X₂ (M=Fe, X=Br or I; M=Co, X=I; M=Ni, X=Cl, Br or NCS) the ligand is chelating in the [M(DADH)₃]²⁺ cations, while in M(DADH)₂X₂ (M=Co, X=Cl or Br; M=Ni, X=Cl or Br) the ligand is probably bridging and bidentate. Diacetylbismonomethylhydrazone (DAMH), by contrast, forms predominantly tetrahedral complexes M(DAMH)X₂ (M=Fe or Co, X=Cl or Br; M=Ni, X=Br; M=Co, X=NCS; M=Zn, X=Cl, Br or NCS) and some octahedral complexes M(DAMH)₂X₂ (M=Co, X=NCS; M=Ni, X=Br). The i.r. spectra, electronic spectra and magnetic moments of the complexes are discussed.     

Heterometallic Mixed‐Valence Copper(I,II) Cyanides that were Tuned by Using the Chelate Effect: Discovery of Famous Cairo Pentagonal Tiling and Unprecedented (3,4)‐Connected {83}2{86} Topological 3D Net

By using environmentally friendly [Ni(CN)₄]^2? as a cyanide source, three new heterometallic cyano‐bridged mixed‐valence Cu^I/Cu^II coordination polymers with three different electronic configurations (d⁸–d¹⁰), that is, [Cu₂Ni(CN)₅(H₂O)₃] ( 1 ), [Cu₂Ni(CN)₅(pn)H₂O] ( 2 ), and [Cu₃Ni(CN)₆(pn)₂] ( 3 , pn=1,2‐propane diamine) have been synthesized by gradually increasing the amount of pn. Compound 1 , which was hydrothermally synthesized in the absence of pn ligand, exhibits the famous 2D Cairo pentagonal tiling, in which the Cu^I, Cu^II, and Ni^II atoms act as trigonal, T‐shaped, and square‐planar nodes, respectively. Notably, there are three water molecules located at the meridianal positions of the octahedrally coordinated Cu^II atom in compound 1 . A similar reaction, except for the addition of a small amount of pn, generated a similar Cairo pentagonal tiling layer in which two of the water molecules that were located at the meridianal positions of the octahedrally coordinated Cu^II atom were replaced by a chelating pn group. Another similar hydrothermal reaction, with the addition of a larger amount of pn, yielded compound 3 , which showed a related two‐fold‐interpenetrated (3,4)‐connected 3D framework with an unprecedented {8³}₂{8⁶} topology in which the Cu^II atom was chelated by two pn groups. These structural changes between compounds 1 , 2 , 3 can be explained by the chelating effect of the pn group. The replacement of two meridianally coordinated water molecules on the octahedral Cu^II atom in compound 1 by a pn group gives compound 2 , which shows similar Cairo tiling, and a further increase in the amount of pn results in the formation of the [Cu(NC)₂(pn)₂] unit and the two‐fold‐interpenetrated 3D framework of compound 3 . The mixed‐valence properties of compounds 1 , 2 , and 3 were confirmed by variable‐temperature magnetic‐susceptibility measurements.     

First row wheels, [((t)Bu(3)SiS)MX](12)(M = Co, X = Cl; M = Ni, X = Br), are common amongst both simpler and more complex aggregates

[((t)Bu(3)SiS)MX[(12) are wheels for first row transition metals (M = Co, X = Cl; M = Ni, X = Br), but for nickel, simpler [e.g. [((t)Bu(3)SiS)Ni](2)(mu-SSi(t)Bu(3))(2)[ and more complicated [e.g. [(mu-SSi(t)Bu(3))Ni](5)(mu(5)-S)] structures are by-products.     

The reactive chemisorption of alkyl iodides at Cu(110) and Ag(111) surfaces: a combined STM and XPS study

The chemisorption of methyl and phenyl iodide has been studied at Cu(110) and Ag(111) surfaces at 290 K with STM and XPS. At both surfaces dissociative adsorption of both molecules leads to chemisorbed iodine, with the STM showing c(2 x 2) and (square root 3 x square root 3)R30 structures at the Cu(110) and Ag(111) surfaces, respectively. At the Cu(110) surface a comparison of coexisting c(2 x 2) I(a) and p(2 x 1) O(a) domains shows the iodine adatoms to be chemisorbed in hollow sites with evidence at low coverage for diffusion in the (110) direction. In the case of methyl iodide no carbon adsorption is observed at either the silver or the copper surfaces, but chemisorbed phenyl groups are imaged at the Cu(110) surface after exposure to phenyl iodide. The STM images show the phenyl groups as bright features approximately 0.7 nm in diameter and 0.11 nm above the iodine adlayer, reaching a maximum surface concentration after approximately 6 Langmuir exposure. However, the phenyl coverage decreases with subsequent exposures to PhI and is negligible by approximately 1000 L exposure, consistent with the formation and desorption of biphenyl. The adsorbed phenyls are located above hollow sites in the substrate, they are stabilized at the top and bottom of step edges and in paired chains (1.1 nm apart) on the terraces with a regular interphenyl spacing within the chains of 1.0 nm in the (110) direction. The interphenyl ring spacing and diffusion of individual phenyls from within the chains shows that the chains do not consist of biphenyl species but may be a precursor to their formation. Although the XPS data shows carbon present at the Ag(111) surface after exposure to PhI, no features attributable to phenyl groups were observed by STM.     

New pincer-type diphosphinito (POCOP) complexes of NiII and NiIII

This communication reports the synthesis and characterization of the new, pincer-type, square-planar, 16-electron compounds {2,6-(OPPr(i)(2))(2)C(6)H(3)}Ni(II)Br, 1, and {(Pr(i)(2)POCH(2))(2)CH}Ni(II)Br, 2, and the square-pyramidal, 17-electron complex {(Pr(i)(2)POCH(2))(2)CH}Ni(III)Br(2), 3.     

Tuning of spin density wave strengths in quasi-one-dimensional mixed-halogen-bridged nickel(III) complexes with strong electron correlation, [Ni(III)(chxn)(2)Cl(1-x)Br(x)](NO(3))(2)

This communication describes the syntheses of the quasi-one-dimensional mixed-halogen-bridged Ni(III) complexes with strong electron correlation [Ni(chxn)(2)Cl(1-x)Br(x)](NO(3))(2) and the tuning of the spin density wave strengths of these compounds. If the Cl 3p and Br 4p make one band in the compounds, we should observe a single peak in the electronic spectra. As a result, we should observe the single peak from 1.45 to 2.00 eV depending on the mixing ratios of Cl and Br ions. Therefore, the Cl 3p and Br 4p make one band. Then, we have succeeded in tuning the spin density wave strengths of the Ni(III) complexes with the strong electron correlation by mixing the bridging halogen ions successively.     

Zur Oxydation von Gemischtligand-Nickel(0)-Komplexen mit organischen Halogeniden

Oxidation of Mixed Ligand Nickel(0) Complexes by Organic Halides The oxidation of (dipy)Ni(PPh₃)₂ by alkyl and aryl iodides or bromides affords the nickel(I) complexes (dipy)Ni(PPh₃)X (X = Br, I). No normal products of oxidative addition are obtained. But in the case of methyl and ethyl halides complexes of the type (dipy)NiR₂ are formed as intermediates. Basing on the identified final products and on the correalation between the reactivity of the organic halides and their polarographic half wave potentials a mechanism of the reaction is proposed. The first step is a charge transfer from nickel(0) to the organic halide. Further synthesis, reactions, and the ESR-spectra of the complexes (dipy)Ni(PPh₃)X and a synthesis of (dipy)Ni(CH₂Ph)₂ are described. Experiments to prepare pure (dipy)Ni(PPh₃)Cl had no success.     

Synthesis and antimicrobial activities of isomers of N(4),N(11)-dimethyl-3,5,7,7,10,12,14,14-octamethyl-1,4,8,11-tetraazacyclotetradecane and their nickel(II) complexes

The reactions of two isomers of 3,5,7,7,10,12,14,14-octamethyl-1,4,8,11-tetraazacyclotetradecane (differing in the orientation of the methyl groups on the chiral carbon atoms), designated as L(B) and L(C), with CH(3)I in the ratio of 1:4 resulted in the substitution of the N(4) and N(11) protons by CH(3) groups, forming the dimethyl derivatives L(BZ) and L(CZ), respectively. These ligands, on interaction with nickel(II) acetate tetrahydrate and subsequent addition of lithium perchlorate, produce square-planar yellow [NiL(BZ)][ClO(4)](2) and orange [NiL(C'Z)][ClO(4)](2). These nickel complexes undergo axial ligand addition reactions with NCS(-), Cl(-), Br(-), and I(-) as X(-) to form six-coordinate trans-diisothiocyanato, -dichloro, -dibromo, and -diiodo complexes of formula [NiLX(2)], where L = L(BZ) or L(C'Z), and X = SCN, Cl, Br, or I. All these compounds have been characterized on the basis of analytical, spectroscopic, conductometric, and magnetochemical data. The structures of L(BZ) and two variants of [Ni"L(BZ)"][ClO(4)](2) (crystallizing in the space group P2(1)/n and Pn, respectively; "L(BZ)" symbolizes partially methylated ligand) have been determined by single-crystal X-ray analyses. The antifungal and antibacterial activities of these compounds have been studied against some phytopathogenic fungi and bacteria.     

Crystal Structure of Ni(NH3)Cl2 and Ni(NH3)Br2

Ni(NH₃)Cl₂ and Ni(NH₃)Br₂ were prepared by the reaction of Ni(NH₃)₂X₂ with NiX₂ at 350 °C in a steel autoclave. The crystal structures were determined by X‐ray powder diffraction using synchrotron radiation and refined by Rietveld methods. Ni(NH₃)Cl₂ and Ni(NH₃)Br₂ are isotypic and crystallize in the space group I2/m with Z = 8 and for Ni(NH₃)Cl₂: a = 14.8976(3) Å, b = 3.56251(6) Å, c = 13.9229(3) Å, β = 106.301(1)°; Ni(NH₃)Br₂: a = 15.5764(1) Å, b = 3.74346(3) Å, c = 14.4224(1) Å, β = 105.894(1)°. The crystal structures are built up by two crystallographically distinct but chemically mostly equivalent polymeric octahedra double chains [NiX_3/3X_2/2(NH₃)] (X = Cl, Br) running along the short b‐axis. The octahedra NiX₅NH₃ share common edges therein. The crystal structures of the ammines Ni(NH₃)_mX₂ with m = 1, 2, 6 can be derived from that of the halides NiX₂ (X = Cl, Br) by successive fragmentation of its CdCl₂ like layers by NH₃.     

Supramolecular Cl⋅⋅⋅H and O⋅⋅⋅H Interactions in Self‐Assembled 1,5‐Dichloroanthraquinone Layers on Au(111)

The role of halogen bonds in self‐assembled networks for systems with Br and I ligands has recently been studied with scanning tunneling microscopy (STM), which provides physical insight at the atomic scale. Here, we study the supramolecular interactions of 1,5‐dichloroanthraquinone molecules on Au(111), including Cl ligands, by using STM. Two different molecular structures of chevron and square networks are observed, and their molecular models are proposed. Both molecular structures are stabilized by intermolecular Cl???H and O???H hydrogen bonds with marginal contributions from Cl‐related halogen bonds, as revealed by density functional theory calculations. Our study shows that, in contrast to Br‐ and I‐related halogen bonds, Cl‐related halogen bonds weakly contribute to the molecular structure due to a modest positive potential (σ hole) of the Cl ligands.     

The Co-CH(3) Bond in Imine/Oxime B(12) Models. Influence of the Orientation and Donor Properties of the trans Ligand As Assessed by FT-Raman Spectroscopy

Near-IR FT-Raman spectroscopy was used to probe the properties of three types of methyl imine/oxime B(12) model compounds in CHCl(3) solution. These types differ in the nature of the 1,3-propanediyl chain and were selected to test the influence of electronic and steric effects on the Co-CH(3) stretching (nu(Co)(-)(CH)()3) frequency, a parameter related to Co-C bond strength. For the first type studied, [LCo((DO)(DOH)pn)CH(3)](0/+) ((DO)(DOH)pn = N(2),N(2)(')-propane-1,3-diylbis(2,3-butanedione 2-imine 3-oxime)), nu(Co)(-)(CH)()3 decreased from 505 to 455 cm(-)(1) with stronger electron-donating character of the trans axial ligand, L, in the order Cl(-), MeImd, Me(3)Bzm, 4-Me(2)Npy, py, 3,5-Me(2)PhS(-), PMe(3), and CD(3)(-). This series thus allows the first assessment of the effect of negative axial ligands on nu(Co)(-)(CH)()3; these ligands (L = Cl(-), 3,5-Me(2)PhS(-), CD(3)(-)) span the range of trans influence. The CH(3) bending (delta(CH3)) bands were observed at 1171, 1159, and 1150/1105 cm(-)(1), respectively. The decrease in C-H stretching frequencies (nu(CH)) of the axial methyl suggests that the C-H bond strength decreases in the order Cl(-) > 3,5-Me(2)PhS(-) > CD(3)(-). This result is consistent with the order of decreasing (13)C-(1)H NMR coupling constants obtained for the axial methyl group. The trend of lower nu(Co)(-)(CH)()3 and nu(CH) frequencies and lower axial methyl C-H coupling constant for stronger electron-donating trans axial ligands can be explained by changes in the electronic character of the Co-C bond. The symmetric CH(3)-Co-CH(3) mode (nu(CH)()3(-)(Co)(-)(CH)()3) for (CH(3))(2)Co((DO)(DOH)pn) was determined to be 456 cm(-)(1) (421 cm(-)(1) for (CD(3))(2)Co((DO)(DOH)pn). The L-Co-CH(3) bending mode (delta(L)(-)(Co)(-)(CH)()3) was detected for the first time for organocobalt B(12) models; this mode, which is important for force field calculations, occurs at 194 cm(-)(1) for ClCo((DO)(DOH)pn)CH(3) and at 186 cm(-)(1) for (CH(3))(2)Co((DO)(DOH)pn. The nu(Co)(-)(CH)()3 frequencies were all lower than those reported for the corresponding cobaloxime type LCo(DH)(2)CH(3) (DH = monoanion of dimethylglyoxime) models for planar N-donor L. This relationship is attributed to a steric effect of L in [LCo((DO)(DOH)pn)CH(3)](+). The puckered 1,3-propanediyl chain in [LCo((DO)(DOH)pn)CH(3)](+) forces the planar L ligands to adopt a different orientation compared to that in the cobaloxime models. The consequent steric interaction bends the equatorial ligand toward the methyl group (butterfly bending); this distortion leads to a longer Co-C bond. In a second imine/oxime type, a pyridyl ligand is connected to the 1,3-propanediyl chain and oriented so as to minimize butterfly bending. The nu(Co)(-)(CH)()3 frequency for this new lariat model was close to that of pyCo(DH)(2)CH(3). In a third type, a bulkier 2,2-dimethyl-1,3-propanediyl group replaces the 1,3-propanediyl chain. The nu(Co)(-)(CH)()3 bands for two complexes with L = Me(3)Bzm and py were 2-5 cm(-)(1) lower in frequency than those of the corresponding [L(Co((DO)(DOH)pn)CH(3)](+) complexes. The decrease in the axial nu(Co)(-)(CH)()3 frequencies is probably due to the steric effect of the equatorial ligand. Thus, the nu(Co)(-)(CH)()3 frequency can be useful for investigating both steric and electronic influences on the Co-C bond.     

Cobalt(II), nickel(II), copper(II), and zinc(II) complexes with [3(5)]adamanzane, 1,5,9,13-tetraazabicyclo[7.7.3]nonadecane, and [(2.3)(2).2(1)] adamanzane, 1,5,9,12-tetraazabicyclo[7.5.2]hexadecane

Isolation of the free bicyclic tetraamine, [3(5)]adamanzane.H(2)O (1,5,9,13-tetraazabicyclo[7.7.3]nonadecane.H(2)O), is reported along with the synthesis and characterization of a copper(II) complex of the smaller macrocycle [(2.3)(2).2(1)]adamanzane (1,5,9,12-tetraazabicyclo[7.5.2]hexadecane) and of three cobalt(II), four nickel(II), one copper(II), and two zinc(II) complexes with [3(5)]adamanzane. For nine of these compounds (2-8, 10b, and 12) the single-crystal X-ray structures were determined. The coordination geometry around the metal ion is square pyramidal in [Cu([(2.3)(2).2(1)]adz)Br]ClO(4) (2) and trigonal bipyramidal in the isostructural structures [Cu([3(5)]adz)Br]Br (3), [Ni([3(5)]adz)Cl]Cl (5), [Ni([3(5)]adz)Br]Br (6), and [Co([3(5)]adz)Cl]Cl (8). In [Ni([3(5)]adz)(NO(3))]NO(3) (4) and [Ni([3(5)]adz)(ClO(4))]ClO(4) (7) the coordination geometry around nickel(II) is a distorted octahedron with the inorganic ligands at cis positions. The coordination polyhedron around the metal ion in [Co([3(5)]adz)][ZnCl(4)] (10b) and [Zn([3(5)]adz)][ZnCl(4)] (12) is a slightly distorted tetrahedron. Anation equilibrium constants were determined spectrophotometrically for complexes 2-6 at 25 and 40 degrees C and fall in the region 2-10 M(-1) for the halide complexes and 30-65 M(-1) for the nickel(II) nitrate complex (4). Rate constants for the dissociation of the macrocyclic ligand from the metal ions in 5 M HCl were determined for complexes 2, 3, 5, 8, 10, and 12. The reaction rates vary from half-lives at 40 degrees C of 14 min for the dissociation of the Zn([3(5)]adz)(2+) complex (12) to 14-15 months for the Ni([3(5)]adz)Cl(+) ion (5).