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Diffuse reflectance spectroscopy was used for the first time to investigate the adsorption of the [Co(H2O)6]²⁺ ions on the interface developed between the surface of the γ-alumina particles and the electrolytic aqueous solutions used for the preparation of cobalt-supported γ-alumina catalysts by equilibrium deposition filtration. The formation of inner-sphere Co(II) surface complexes in which Co(II) is in octahedral symmetry was confirmed. A deconvolution peak centered at ~585 nm was attributed to the exchange of one aqua ligand with one AlxOHy (x = 1, 2, or 3; y = 0 or 1) negatively charged surface group resulting in the formation of mononuclear monosubstituted inner-sphere Co(II) complexes at a Co(II) surface concentration equal to 0.02 μmol of Co(II)/m². It was inferred that as the surface Co(II) concentration increases the formation of disubstituted and/or trisubstituted surface complexes is favored with respect to the formation of monosubstituted Co(II) surface complexes. A deconvolution peak centered at ~640 nm was attributed to the exchange of one or more aqua ligands with bridging hydroxo ligands (Co−O−H). The relative magnitude of this peak increases with the Co(II) surface concentration, reflecting the increasing formation of binuclear, oligonuclear, and multinuclear Co(II) surface complexes and then the formation of the Co(II) surface precipitate.

Complexes of the general formula M(LH2)Cl2· 2 H2O, where LH2= N,N′-(dipicolyl)-1,8-naphthylenediamine and M = Mn, Ni and Cu, have been prepared. None of the metal ions used promote amide deprotonation on coordination: LH2acts as a tetradentate ligand.

The preparation of sixteen new etherate, pyridine and aniline compounds of complex halo and pseudohalo acids of Zn(II) is reported.

Synthetic procedures are described that allow access to anilinium salts containing the complex anions [Hg2Cl62-, [Hg2Cl4X2]2-(X = Br, I), [CdHgI6]2-, [CdHgI4Br2]2-and [CdHgBr4I2]2--. Isolated dimeric structures are proposed for the new complexes in the solid state, using X-ray powder patterns, Far-IR and Raman spectra. The spectral detail is greatly enhanced in measurements at low temperature (∼100 K).

The preparation, for the first time, of the deprotonated complexes of oxamic acid with Ce(III), Pr(III), Nd(III), Sm(III), Eu(III), Dy(III), Ho(III) and Yb(III) is reported. Properties, analytical results, conductometric measurements, magnetic moments and spectral data (IR and diffuse reflectance spectra) are discussed in terms of possible structural types and the nature of the bonding. Oxamic acid acts as a bidentate non-bridging ligand.

The new complexes K2[ML2] (M = ═Mn, Cu), K2[ML2(H2O)2] (M = Co, Ni), K2[Cu2L2(OH)2] and K2[Cu2L2(OH)2(H2O)4], where LH2= Bis(o-aminobenzenesulfonyl)ethylenediamine, have been prepared. Properties, X-ray powder patterns, molar conductance measurements, magnetic moments and spectral (IR, diffuse reflectance, visible in solution) data are discussed in terms of possible structural types and the nature of the bonding.

New complexes of the general compositions Ln(o-LH)3·2H2O (Ln=La, Ce, Pr, Nd, Sm), Er(o-LH)3·2.5H2O, Ln(o-LH)3·3H2O (Ln=Eu, Gd, Tb, Dy, Ho, Tm, Yb), Ln(m-LH)3·2H2O (Ln=Pr, Nd, Sm, Gd, Er), Ln(m-LH)3·3H2O (Ln=La, Ce, Eu, Tb) and Ln(m-LH)3·4H2O (Ln=Dy, Ho, Tm, Yb), where o-LH2=N-(2-carboxylphenyl) pyridine-2' -carboxamide and m-LH2=N-(3-carboxylphenyl)pyridine-2' -carboxamide, have been isolated. The complexes, which are probably polymeric, were characterised by elemental analyses, conductivity measurements, thermal (TG, DTG, DTA, DSC) methods, X-ray powder patterns, magnetic moments and spectral (IR, Raman, 1H-NMR, electronic diffuse reflectance and emission f-f spectra) studies. All the data are discussed in terms of the nature of the bonding and the possible structural types. The neutral secondary amide group and the ring N-atom of o-LH-and m-LH- are not coordinated to the metal ions. The carboxylate

New complexes of the general compositions M(LH2)2X2 (M = Co, Ni, Cu, Zn; X = Cl, NCS, NO3), M(LH2)2Cl2. EtOH (M = Ni, Cu; EtOH = ethanol), M(LH)2.nH2O (M = Co, Ni, Cu, Zn, Pt; n = 1, 2, 3), Pd(LH)Cl·H2O, CuL·3H2O and Zn(LH) (OH) ·2H2O, where LH2 = N-(3-carboxylphenyl)pyridine-2'-carboxamide, have been isolated. The complexes were characterised by elemental analyses, conductivity measurements, TG patterns, magnetic susceptibilities and spectral (1H-NMR, IR, electronic) studies. Distorted octahedral and square planar stereochemistries are assigned in the solid state. Coordination of the neutral carboxylic group is not observed for the complexes of LH2; the carboxylate ion exhibits monodentate coordination in the compounds of LH- and L2-. The neutral amide group of LH2 and LH- is coordinated to Co(II), Ni(II), Cu(II) and Zn(II) through oxygen, while nitrogen and oxygen amide coordination is observed for CuL·3H2O. The secondary amide bond shows the rare iminol type of coordination in Pd(LH)Cl·H2O.

The complexes [Coiii(LH2)3]X3 (LH2 = dithiooxamide, N-methyldithiooxamide, N,N'-dimethyldithiooxamide; X = Cl, Br, l) and [CoiiL]n have been prepared. They were characterized by analyses, thermal techniques, magnetic susceptibilities and spectroscopic (ligand-field, 13C-NMR, FT-IR) methods. The vibrational analysis of the prepared complexes is given using NH/ND and CH3/CD3 isotopic substitutions. The neutral dithiooxamides exhibit a bidentate chelating S,S-coordination, while the doubly deprotonated dithiooxamido anions act as bis-bidentate bridging S,N/N,S-ligands giving trans polymeric structures. The Co(III) complexes are octahedral with CoIIIS6 coordination spheres. A square planar geometry around Co(II) is assigned for the polymeric compounds.

The new complexes CuX2(LH2), CuX2 (SH3) (X = Cl, Br), CuX(LH2), CuX(SH3) (X = Cl, Br, I), CuX(H4MTO)2 (X = Cl, Br), Cul(H4MTO) and CuX(H3MMTO)2 (X = Cl, Br, I), where LH2 = N.N'-dimethyl-monothiooxamide, SH3 = N(s)-methylmonothiooxamide, H4MTO = monothiooxamide and H3MMTO = N(o)-methylmonothiooxamide, have been prepared. The complexes were characterized by elemental analyses, conductivity measurements, magnetic moments and spectroscopic (UV/VIS, FT-IR, Laser-Raman) studies. The vibrational analysis of the complexes has been given using NH/ND, CH3/CD3 and 63cu/65cu isotopic substitutions. The neutral monothiooxamides behave as monodentate ligands in the Cu(I) complexes coordinating through their thioamide sulfur atom. The ligands LH2 and SH3 act as bidentate chelating agents in the Cu(II) complexes with ligated atoms being the thioamide sulfur and the amide oxygen.

The new complexes trans-[PdX2(H4MTO)2] (X = Cl, Br, I), trans-[PdX2(H3MMTO)2] (X = Cl, Br, I), trans-[PdX2(SH3)2] (X = Cl, Br), [Pd(H4MTO)4]CI2 and [Pd(H3MMTO)4]CI2, where H4MTO = monothiooxamide, H3MMTO = N(o)-methylmonothiooxamide and SH3 = N(s)-methylmonothiooxamide, have been prepared. The complexes were characterized by elemental analyses, conductivity measurements, X-ray powder patterns, thermal methods and spectroscopic (UV/VIS, FT-IR, Laser-Raman) studies. The vibrational analysis of the complexes is given using NH/ND and CH3/CD3 isotopic substitutions. Monomeric square planar structures are assigned for the complexes in the solid state. The neutral monothiooxamides behave as monodentate ligands coordinating through their thioamide sulfur atom. The complex [Pd(SH2)2] was isolated during the thermal decomposition of trans-[PdCl2(SH3)2].

The preparation, for the first time, of the complex iodo acids of mercury (II) with ether and pyridine of the formula H[HgI3]2B (where B = ether or pyridine) is described. The chemical and physical properties of these acids and the UV and IR spectra of the pyridine compound are reported and discussed.

The preparation of the new compound N,N′-(dipicolyl)1,8-naphthylenediamine = DPNAP is reported which can serve as a tetradentate ligand.

The preparations of new compounds, containing the complex anions [Hg2l5]-, [Hg2l6]2-and [Hg3I8]2-, are reported.

A variety of new complexes of the title ligand exhibiting a wide range of different structures are prepared by reaction of the ligand with the metal salt in water at pH 6.0‐6.5 (applied for (I), (II), (IV) and (VI)) or pH 10.0‐10.5 (applied for (V) and (VII)) or in absolute EtOH (applied for (III), (VIII) and (IX)).

N‐(2‐aminophenyl)pyridine‐2'‐carboxamide in EtOH and the appropriate Co(II) salts in water react at 50 °C within 5 h to give the complexes (Ia); the same procedure carried out with anhydrous salts leads to the compounds (Ib).

The new light‐sensitive complexes (I)‐(IV) are prepared by reaction of the ligand in water with an equimolar amount of NaOH and the appropriate metal chloride in a yield of 65‐80%.