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We report the synthesis and characterization of a seven coordinate europium complex, [EuCl3(C10H8N2O2) AE 2CH3OH]. The growing interest in developing efficient light conversion molecular devices (LCMDs) necessitates the need for new fluorescent materials. Ideal physicochemical properties of the materials include ligand absorption, efficient metal to ligand transfer, and strong luminescence with a relatively long decay time. The design of such material requires distinct absorbing (ligand) and emitting (metal ion) components. While Eu 3+ cation has a non-degenerate emitting level, 2,2 0 -bipyridine N,N dioxide is a heterocyclic ligand known to exhibit strong lumines

The title compound, [HgI2(C10H8N2O2)], is a further example of a mercury halide complex of the chelating BipyO2 ligand (BipyO2 is 2,2′-bipyridine N,N′-dioxide). As observed for similar compounds, the coordination polyhedron of the Hg atom is a severely distorted tetrahedron, in which Hg is coordinated by two I atoms and two O atoms of the ligand.

In the crystal structure of the title compound, [HgCl2(C10H8N2O2)], the Hg atom has severely distorted tetrahedral coordination by two Cl atoms and by two O atoms of the chelating ligand. Additional weak Hg⋯Cl bonds link the mol­ecules into a chain.

A series of metal perclorate complexes of N- isopropyl-2-pyrrolidinone (NIPP) and N-cyclohexyl- 2-pyrrolidinone (NCHP) have been synthesized, showing coordination through the carbonyl oxygen atom. These complexes have compositions with the general formulas [M(NIPP)4 or 6]2+(ClO4)2 and [M(NCHP)6]2+(ClO4)2 [M = Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II)]. They have been characterized by IR spectra, electrical conductivity measurements, magnetic moments, X-ray diffraction patterns and electronic absorption spectra.

Under carefully controlled experimental conditions, a series of metal nitrate complexes of dibenzylsulfoxide (DBSO) have been synthesized and isolated (for the dipositive Co, Ni, Cu and Zn elements). The compounds were characterized by use of infrared-, ultraviolet-, and visible spectra. Their stoichiometric compositions appeared to be [M- (DBSO) 3 (NO 3 ) 2 ], where MCo, Ni and Cu; and [M(DBSO) 3.5 (NO 3 ) 2 ], where MZn. The additional information concerning the nature of bonding and structural geometry was derived from X-ray diffraction analysis, molecular conductivities, molecular weight and magnetic susceptibility measurements. The infrared spectra indicated that, in all cases, coordination occurred through the oxygen atom of the DBSO ligand. Both analyses and spectral studies suggest that the transition metal ions manifest a coordination number of six. The slight decrease in metal ion radius across the first transition metal series does not affect the number of DBSO molecules bonded to the M 2+ ion, but the only variation in total coordination of cation might be attributed to the DBSO competition with nitrato groups for the coordination site due to the ability of the anion to enter the coordination sphere.

The tittle bidentate sulfoxides have been synthesized and employed as ligands toward Mn +2 , Co +2 , Ni +2 , Cu +2 and Zn +2 . The resulting complexes were characterized by analyses, magnetic measurements visible and infrared spectra. All metal ions are bound to the ligands via the oxygens of the sulfoxide groups and are 6-coordinate with the exception of Cu +2 , which is 4-coordinate. Crystal field calculations for the Ni +2 species indicate a slight decrease in filed strength with an increase in the number of CH 2 groups between the sulfoxide functions and also with increasing size of the substituent attached to the sulfur.

The main emphasis in the study has been the investigation of the kinetics of the stepwise reactions of [Co(tren)C2O4]+ ion [tren = 2,2’,2”-triaminotriethylamine, N(CH2CH2NH2)3] in both dilute and concentrated acids, as well as the characterization in solution of some new Co(III) tren complexes. The aquation reaction was conducted in 1.0 M HClO4 solution under various conditions. Protonation of a carbonyl oxygen in the complex appeared to increase the lability of the Co—O moiety, leading to a unidentate oxalate ligand. The stepwise anation of [Co- (tren)C2O4]+ to [Co(tren)Cl2]+ in concentrated HCl was also followed. Both systems react by a dissociative reaction mechanism.

A new series of dibenzylsulfoxide (DBSO) compounds of empirical formula [Ln(DBSO)x(NO3)3] are reported, where x = 3 for Ln = Pr; x = 2.5 for Ln = Nd, Sm, Eu, Gd, Er and La; and x=2 for Ln = Dy. The compounds were synthesized from a non-aqueous solvent and isolated as dibenzylsulfoxide salts. Infrared spectral data established coordination by the anion groups and also that coordination of DBSO is through the oxygen. Additional information based on the nature of bonding and geometrical structure was obtained from the electronic absorption spectra, X-ray diffraction analysis, molecular conductivities and molecular weight measurements (as well as magnetic susceptibility measurements). All these physical measurements indicate octahedral coordination. The 20% decrease in the metal ion radius across the lanthanide series and the competition between DBSO and nitrate groups for the coordination site affect the number of DBSO molecules bonded to a tripositive lanthanide ion.

The complexes SbCl 3 (TMSO) 2 , SbBr 3 (TMSO) 2 , BiCl 3 (TMSO) 3 , BiBr 3 (TMSO) 3 , ZnCl 2 (TMSO) 2·5 , CdCl 2 (TMSO) 1·5 , CdCl 2 (TMSO), and HgCl 2 (TMSO) 1·5 (TMSO = tetramethylene sulfoxide) have been prepared and investigated spectroscopically. The near and far i.r. and Raman assignments for the solids are discussed with emphasis on the metal-halogen and metal-oxygen vibrations. All molecules are shown to be coordinated through the oxygen, as indicated by the ligand frequency shifts to lower frequencies. Structure considerations for the solid-state species are discussed.

The kinetics of the primary acid hydrolysis reaction of [Rh(tren)Cl 2 ] + ion [tren = β,β′,β″-triaminotriethylamine, N(CH 2 CH 2 NH 2 ) 3 ] were studied between 25 and 60·3°. The pseudo-first-order rate constant for the release of one chloride ion at 60·3° in 0·1 M HClO 4 was found to be 1·14 × 10 −3 sec −1 . This rate constant was independent of the initial concentration of the complex over the range of 0·58–1·9 mM and of pH from 1 to 5. Activation parameters were ΔH ∗ = 18·7 ± 0·8 kcal mole −1 and ΔS ∗ = −16·0 ± 2·0 cal deg −1 mole −1 . No evidence was found for a second aquation step.

Several new hexahalo complexes of the formulas [N(CH2CH2NH3)3][MX6] (M = Rh, Ir; X = Cl, Br) and [N(CH2CH2NH3)3][RhCl3Y3] (Y = Br, l) were prepared. The complexes were characterized by elemental analysis, infrared and electronic spectra.

Coordination compounds with 2,2′-bipyridine-1,1′-dioxide (bipyO2) having the composition [UO2(bipyO2)2(NO3)2]·4H2O, [Pr(bipyO2)4(NO3)2]NO3·2H2O, [Dy(bipyO2)4(NO3)2]NO3·4H2O and [Er(bipyO2)4(NO3)2]NO3·4H2O have been synthesized. These new complexes have been characterized by electrical conductance, X-ray powder patterns and IR spectral measurements. IR spectra indicate that M ← bipyO2 (M = oxycation or metal ion) in these complexes appears in the region of 350–373 cm−1.

The kinetics of the primary acid hydrolysis of [Co(tren)Cl 2 ]Cl· 1 2 H 2 O have been measured in methanol- and ethanol-water mixtures of alcohol mole fractions 0.05, 0.10, 0.15 and 0.20. In all the solvents investigated the primary acid hydrolysis occurs via a dissociative mechanism. The rate constants and thermodynamic activation parameters were determined. The dependence of the rate constant of the mole fraction, dielectric constant and ionizing power of the solvent was investigated.

The syntheses and physical properties of a series of new compounds of the general formula Ln2(n-PSO)11(ClO)6 (where Ln = Gd, Dy and Er; n-PSO = di-n-propylsulfoxide) are reported. IR spectra show coordinated perchlorato groups, and indicate that coordination of n-PSO is through the oxygen. For all of the complexes the IR, Raman and visible spectra are reported, as well as the molar conductivities, X-ray powder patterns and molecular weights.

Complexes of the formulas [Co(NIPP)4](ClO4)2 and [Co(NIPP)6](ClO4)2 have been synthesized and isolated (NIPP = N-isopropyl-2-pyrrolidinone). IR spectra and conductance data are presented as proof that perchlorate coordination in [Co(NIPP)4](ClO4)2 does not occur. Vibrational spectra indicate that coordination occurs through the NIPP carbonyl oxygen for both complexes. Spectral parameters obtained from the electronic spectra and magnetic moments indicate tetrahedral and octahedral coordination for [Co(NIPP)4](ClO4)2 and [Co(NIPP)6](ClO4)2, respectively. The powder X-ray diffraction data appear to support the assignments of these two geometries. The crystal-field prediction that Δ(Td)/Δ(Oh) = 0.44 is in reasonably good agreement with the experimental results.

The syntheses and physical properties of the crystalline compounds [Eu(bipyO2)4](ClO4)3 and [Tb(bipyO2)4](ClO4)3(bipyO2-2,2′-bipyridine, 1,1′-dioxide) are reported. The compounds are characterized by i.r. spectra and conductance measurements. Both complexes are observed to fluorescence in both the solid state and in nitromethane solution, and the fluorescence spectra for both the europium and terbium complexes in solution are reported.

The preparation of several new octahedral cobalt(III) complexes of the type [Co(tren) X 2 ] A (tren = β, β′, β″-triaminotriethylamine; X = NO 2 , NCS; N 3 ; A = anion) is reported, as well as those of several mixed complexes of the type [Co(tren) XY ] A ( X = NO 2 , NCS; Y = F, Cl, Br; X = Cl, Y = Br). The chelating anion C 2 O 4 2− forms a complex with the formula [Co(tren)C 2 O 4 ] A . The visible spectra of some of the tren complexes in water, and as Nujol mull indicate that the average ligand field around the cobalt ion can be higher or lower than in the corresponding ethylenediamine complexes, depending upon the nature of the cis anionic ligands. The i.r. spectra of the complexes [Co(tren)BrClO 4 ]Br.H 2 O and [Co(tren) X SO 4 ].H 2 O ( X = Cl, Br) indicates that the perchlorate and sulfate ions are coordinated in the solid state.

The syntheses and physical properties of crystalline lanthanide complexes, La(TMSO)4− (NO3)3 (TMSO = tetramethylene sulphoxide), Ln2(TMSO)7(NO3)6 (Ln = Nd, Sm) and Ln2(TMSO)6− (NO3)6 (Ln = Gd, Dy, Er, Yb) are reported. The i.r. spectra, molar conductivities, molecular weights and X-ray powder patterns are also included. The i.r. spectra indicate that, in all cases, co-ordination occurs through the oxygen atom of TMSO, and all nitrate groups are co-ordinated in the solid state. The co-ordination number is believed to be eight and the nitrate co-ordination changes from predominantly monodentate to predominantly bidentate across the period.

The syntheses and properties of the crystalline compounds, [CoL 2 X 2 ] (L = e-thiocaprolactam) (X = Cl, Br, I) and [CoL 4 ](ClO 4 ) 2 ; are reported. The spectral parameters Dq , B ′ and β are calculated for the sulphur-co-ordinated complexes. The data indicate tetrahedral stereochemistry for these complexes. e-Thiocaprolactam is assigned a position relative to the other sulphur-containing donors in the spectrochemical series. Infra-red spectra indicate that Co ← S bond in these complexes appears at 390 cm −1 .

The preparation and properties of the crystalline compounds [Co(DMTA)2X2](DMTA = N,N-dimethylthioacetamide) (X = Cl, Br, I, NO3) and [Co(DMTA)4] (ClO4)2 are described. The ligand field parameters Dq, B′ and β are calculated for the tetrahedral, sulphur-co-ordinated complexes. The electronic spectra and magnetic measurements support tetrahedral stereochemistry. The complex isolated from the reaction of cobalt (II) nitrate and N,N-dimethylthioacetamide is probably octahedral in solution and seems to possess a tetrahedral stereochemistry in the solid state. Spectral data in this study places this ligand at the lower end of the nephelauxetic series.

Complexes SbCl3(BuL)2, SbBr3(BuL)2, BiCl2(BuL)2.5, and HgCl2(BuL) (BuL = γ-butyrolactam) have been prepared and investigated spectroscopically. Infrared and Raman assignments for the solids are discussed, with special emphasis on metal-ligand vibrations. All BuL molecules are shown to be coordinated through oxygen, as indicated by the internal ligand frequency shifts. Structure considerations are presented for the solid-state species.

The syntheses and physical properties of the crystalline compounds [Ln(OMPA) 2 (NO 3 ) 3 ] (Ln = Gd, Er, Yb) are reported. For most of the complexes, the i.r. and Raman spectra, molar conductivities, mol. wt., and X-ray powder patterns are reported. I.R. spectra of these complexes indicate that in the solid state, the complexes contain coordinated nitrate, and in all cases, coordination through the oxygen atom of OMPA is observed. Both the composition of these compounds and the X-ray data clearly indicate the existence of two isomorphous series of OMPA complexes.

The preparation of 26 metallic complexes of 14 different metals with N,N- dimethylacetamide (DMA) is reported. The complexes were characterized by their melting points, infrared spectra in the 2 to 15 mu region, electrical conductance in DMA, and magnetic moments. The infrared spectra suggest that coordination through the oxygen of DMA occurs for all the metals investigated. In most instances, the complexes contain fewer moles of DMA than the maximum coordination number of the metal, indicating coordination by halide ion and/or water. (auth)

The syntheses and physical properties of the crystalline compounds [Ln(BuL)8](NO3)3 (Ln  La, Nd, Gd) (BuL = γ-butyrolactam), and [Ln(BuL)3(NO3)3] (Ln  Dy, Er, Yb) are reported. Infra-red spectra of these complexes indicate that in the solid state the La, Nd, and Gd complexes contain ionic nitrate, while the Dy, Er, and Yb complexes contain covalent nitrato groups. Both molecular weight and conductance data indicate that the complexes containing ionic nitrate dissociate in solution. Both analyses and spectral studies indicate that the larger lanthanide ions have coordination numbers of eight, while the smaller lanthanides are seven coordinated.

The preparation and properties of a series of crystalline nickel(II) complexes of the general formulas [Ni(TBuL) 4 ](ClO 4 ) 2 , Ni(TBuL) 6 (NO 3 ) 2 , [Ni(NMTBuL) 4 ](ClO 4 ) 2 , [Ni(NMTBuL) 2 (NO 3 ) 2 ], [Ni(TBuL) 2 X 2 ] and [Ni(NMTBuL) 2 X 2 ] (TBuL = γ-thiobutyrolactam, NMTBuL = N-methyl-γ-thiobutyrolactam and X  Cl, Br, I) are reported. The chloro-TBuL complex exists in a blue and yellow form. The [Ni(TBuL) 4 ](ClO 4 ) 2 is square planar, whereas Ni(TBuL) 6 (NO 3 ) 2 is diamagnetic. The ligand field parameters Dq , B′ and β are calculated for the remaining complexes of these series. The parameters indicate that most of these complexes are pseudo-tetrahedral and sulphur coordinated. The spectral, i.r., magnetic and electrical conductivity data are utilized in deducing the structures of these complexes. The blue chloro-TBuL complex is considered to be tetrahedral but the yellow chloro-TBuL complex seems to possess a distorted octahedral stereochemistry. With NMTBuL-nickel(II) complexes, a steric effect is observed rather than the inductive effect which was previously observed for the corresponding cobalt(II) complexes.

A series of metal complexes of γ-butyrolactam (BuL) and N-methyl-γ-butyrolactam (NMBuL) have been synthesized, showing co-ordination through the oxygen atom. The perchlorate salts of these complexes have a composition of the general formulas [M(BuL) 6 ] n + (ClO 4 ) n , and [M(NMBuL) 4 or 6 ] n + (ClO 4 ) n (M = Cr 3+ , Al 3+ , Fe 2+ , Mn 2+ , Co 2+ , Ni 2+ , Cu 2+ , Cd 2+ , Zn 2+ , Ca 2+ , Mg 2+ ). The halide complexes of the Co 2+ , Cu 2+ , Mn 2+ and Fe 3+ show, however, a marked structural difference from the perchlorate complexes. The Co(II) halides exhibit the general formula [Co(BuL) 6 ][CoX 4 ] (X = Cl, Br, I and SCN), indicating octahedral cationic and tetrahedral anionic species. The Cu(II) and Mn(II) chlorides have structures of the general formula [M(BuL) 2 Cl 2 ] and [M(BuL)Cl 2 ]. A complex having the formula [Mn(NMBuL)Cl 2 ] has also been isolated. The Fe(III) chloride complex exhibits the structure of the type [FeL 4 Cl 2 ][FeCl 4 ]. These complexes have been characterized by their i.r. spectra, electrical conductivity measurements, magnetic moments, X-ray diffraction patterns and electronic absorption spectra. The ligand field parameters Dq , B′ and β have been calculated for the octahedral cobalt(II) perchlorate complexes, and the tetrahedral [CoX 4 ] 2− species, verifying the proposed geometries and confirming the previously suggested donor order of BuL > NMBuL in the spectrochemical series.

The stoichiometry and kinetics of the acid hydrolysis reaction of Co(tren)ClBr − (tren = β,β′,β″-triaminotriethylamine) in 0.1 M HClO 4 have been investigated. In the acid hydrolysis process the data are consistent with two parallel reactions, probably due to the presence of two isomers in the reactant. One reaction is the release of Cl − in the α-isomer, and the other is the release of Br − in the β-isomer. The pseudo-first-order rate constants for these reactions in 0.1 M HClO 4 at 25.0°C were found to be 3.21 × 10 −3 sec −1 (k α ) and 3.38 × 10 −2 (k β ), respectively. Both rate constants were independent of the acid concentration below pH value 6, and independent of ionic strength from 0.10 to 0.15. Added sulfate ion accelerates the reaction rate. The activation enthalpies and entropies were calculated: ΔH α * = 18.3± 08 kcal mol −1 , ΔH β * = 16.0±0.2 kcal mol −1 ; and ΔS α * = −13.5±2.7 cal mol −1 deg −i , ΔS β * = −9.0±0.7 cal mol −1 deg −1 . The relative rate constants (k β /k α = 10) provide further evidence of the effect of steric strain and crowding on the reactivities of dihalo cobalt(III) tren complexes.

The syntheses, conductance measurements, molecular weight measurements, i.r. spectra, magnetic susceptibilities and electronic spectra of a series of transition metal nitrate complexes of γ-butyrolactam (BuL) are reported. The ligand field parameters Dq, B′, and β are calculated for some of these complexes. The trends of nitrate vs. BuL as competing ligand for nickel(II) ion are discussed.

The syntheses and physical properties of the crystalline compounds [Ln(BuL)8](ClO4)3 (Ln = La, Pr, Nd, Sm, Gd, Dy, Er, Yb, Y) (BuL = γ-butyrolactam), [Ln(NMBuL)8](ClO4)3(Ln = La, Pr, Nd, Sm, Gd) (NMBuL = N-methyl-γ-butyrolactam), and [Ln(NMBuL)7](ClO4)3 (Ln = Dy, Er, Yb, Y) are reported. For most of the complexes the infrared, visible, and ultraviolet spectra are reported, as well as the magnetic susceptibilities, molar conductivities, X-ray powder patterns, and molecular weights. Both the composition of these compounds and the X-ray data indicate clearly the existence of two isomorphous series of NMBuL-complexes, one including compounds of the formulas [Ln(NMBuL)8](ClO4)3 and other compounds of the formulas [Ln(NMBuL)7](ClO4)3.

The synthesis and physical properties of a series of new compounds of the general formula Ln(bipyO 2 ) 4 (ClO 4 ) 3 (where Ln = La, Pr, Nd, Sm, Gd, Dy, Ho, Er, Yb, Y; bipyO 2 = 2,2′-bipyridine 1,1′-dioxide) are reported. Infrared spectra indicate that coordination is through the oxygen. Infrared spectra, as well as conductance measurements indicate that the metal ← bipyO 2 bond is weaker in the lanthanide complexes than in the similar transition metal complexes.

Co-ordination compounds with 2,2′-bipyridine-1,1′-dioxide(bipyO2) having the composition [ZrO(bipyO2)3](ClO4)2·2H2O, [Th(bipyO2)4](ClO4)4, [VO(bipyO2)2](ClO4)2, [UO2(bipyO2)2](ClO4)2, [Mo2O4Cl2(bipyO2)2]·2H2O and [Mo2O3Cl4(bipyO2)2]·2H2O have been synthesized. These new compounds have been characterized by infra-red spectra, electronic absorption spectra, magnetic moments and electrical conductance. Infra-red spectra indicate that M ← L bond (M = oxycation or metal ion, L = Ligand) in these complexes appears between the region 355 cm−1 to 430 cm−1.

The syntheses and physical properties of the crystalline compounds [Ln(HMPA)3(NO3)3] (Ln = La, Nd) (HMPA = hexamethylphosphoramide), [Ln(HMPA)4(NO3)2](NO3) (Ln = Dy, Er, Yb) and dimeric [Ln2 (HMPA)7(NO3)5] (NO3) (Ln = Sm, Gd) are reported. For most of the complexes, the infrared and Raman spectra, molar conductivities, molecular weights and X-ray powder patterns are reported. Infrared spectra of these complexes indicate that in the solid state, the La and Nd complexes contain coordinated nitrate, while the Sm, Gd, Dy, Er and Yb complexes contain both ionic and coordinated nitrate; in all cases coordination through the oxygen atom of HMPA is observed. Both the composition of these compounds and the X-ray data clearly indicate the existence of 3 isomorphous series of HMPA complexes.

The bromide anation reaction of diaquo(triaminotriethylamine)cobalt(III) ion has been studied spectrophotometrically. The kinetics fit a rate law -d[complex] dt =kAN[Br−][complex] kAN typically 10−4 sec−1 M−1. The activation parameters: ΔH* = 25.2±0.4 kcal/mol−1, ΔG* = 24.3±0.3 kcal/mol−1, and ΔS* = 0.19±1.1 cal deg−1 mol−1 at ionic strength 2.0 M.