Charge Transfer (CT) complexes formed between dibenzo-24-crown-8 (DB24C8) as an electron donor with the σ-electron acceptor iodine (I2) in chloroform, dichloromethane, and 1,2-dichloroethane solutions have been studied by different spectroscopic techniques at room temperature. The spectral studies of the complexes were det...

the complexation reactions between methylthymol blue (mtb) and co2+, ni2+, cu2+, zn2+ and pb2+ ions have been studied in different water-methanol mixtures at ph 4.45 and 25 °c by a spectrophotometric technique. the stepwise stability constants of the resulting 1:1 and 2:1 (metal ion to ligand) complexes were determined from the absorbance-mole ratio data. it was found that the overall stability...

the stability constants and complexation reaction between l-glutamine, l-arginine andglycine with zn (ii) , co (ii) and ni (ii) were studied potentiometrically in aqueous solution at25° c and μ=0.1 m kno3. the overall stability constants log β´s of all species are obtained bycomputer refinement of ph-volume data using best computer program. several models weretested and the lowest δfit, the bes...

The stability constants of Cu'(l1) glycine complexes in 0.7 M NaC104 and 0.7M NaN03 media were evaluated using Cu ( 1 1 ) ion selective electrode. The stability constant data are consistent with earlier reports of other metal ion complexes of glycine. The distribution level of Cu ( 1 1 ) glycine complexes in presence of other complexing ligands of marine environment has also been numerically ev...

a competitive spectrophotometric method has been used for the study of complexation between cu2+, zn2+ and cd2+ (m) and 18-crown-6(18c6, b) in methanol using 4-(2-thiazolylazo) resorcinol (tar, hl) as the colorimetric complexant. absorption spectra of the species in the m-tar-18 c6 system at a various concentrations of 18c6 showed no formation of ternary complex, mlb, and the stoichiometry of t...

acid complexes were determined. The dissociation constants of the amino acids determined are; alanine (10.29), arginine (12.02), asparagine (9.39), glycine (9.87), histidine (7.01), lysine (9.28), methionine (9.68), phenylalanine (9.61), proline (10.53), threonine (10.31), tryptophan (9.77), and valine (10.28). The ratio of metal to amino acid determined for the complexes is 1:3, except for Cu ...

in this research some mathematical calculations has been explained on the “ +vo2 +glycylglycine” system and some equations has been deduced to determine the stability constants ofthe equilibrium models including mlh+, ml and ml2h species (while m+ ≡ +2 vo , h2l+ ≡protonated glycylglycine and mlh+, ml and ml2h represent the considered complexes). thecalculations are based on some relations betwe...