The acidity and stability constants of M(Trp) M: Cu, Cu(Bpy)2+, and Cu(Phen)2+ complexes, were determined by potentiometric pH titration. It is shown that the stability of the binary Cu(Trp) complex is determined by the basicity of the carboxylate group on one side and amino group on the other side. It is demonstrated that the equilibrium, Cu(Har)2+ + Cu(Trp) Cu(Har)(Trp) + Cu, is displacement ...

In this study the binding abilities of 1,3-calix[4]biscrown-6 (L) toward Ba2+ and Ca2+ have beenestablished in methanol by spectrophotometric measurements at 25±0.1 °C and 0.01 M ionicstrength, and with using Specfit computer program; stability constants for 2 : 1, metal : ligandcomplexes has been estimated

the formation of charge-transfer complexation between dibenzo-15-crown-5 (db15c5) and benzo-12-crown-4 (b12c4) (donor) and iodine is investigated spectrophotometrically in three chlorinated solvents,chloroform, dichloromethane (dcm) and 1,2-dichloroethane (dce) solution at 25°c. the change in polarityof the solvent also doesn’t affect the stoichiometry of the complexes. values of formation cons...

A critical analysis of the conditions elastic stability crystal structures different symmetry as restrictions imposed on their constants c ij has been carried out. It is shown that all crystals, except for cubic ones, are described by polynomials from second to sixth powers . Necessary and sufficient crystals presented explicitly. Keywords: Elastic stability, Symmetry, constants, Stability cond...

Logarithms of stability constants, log K₁ and log β₂, of the first transition series metal mono- and bis-complexes with any of four aliphatic amino acids (glycine, alanine, valine and leucine) decrease monotonously with third order valence connectivity index, ³χv, from Cu²+ to Mn²+. While stability of the complexes with the same metal is linearly dependent on ³χv, stability constants of Mn²+, F...

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 absorban...

in this study the binding abilities of 1,3-calix[4]biscrown-6 (l) toward ba2+ and ca2+ have beenestablished in methanol by spectrophotometric measurements at 25±0.1 °c and 0.01 m ionicstrength, and with using specfit computer program; stability constants for 2 : 1, metal : ligandcomplexes has been estimated

in this work, we investigated the stability of molybdate-phosphonic acid (mpa) complex by density functionaltheory (dft) computations in six solvents with the dielectric constant ranging from 1.92 to 10.36. the methodsare used for calculations are b3lyp and b3pw9 i that have been studied in two series of basis sets: d95nand6-31+g (d,p) for hydrogen and oxygen atoms; lanl2dz for mo and phosphoru...

Stepwise formation constants of folic acid, N[p[ [ (2-amino-4-hydroxy-6-pteridyl) methyl] ami­ no] benzyl] glutamic acid, with the carcinogenic metal ions, aluminium (III) , chromium (III) , beryl­ lium (II) , lead (II) and uranium (VI) have been determined at 30 °C, and at various ionic strengths, viz. 0.01 m, 0.05 M, 0.10 m, maintained by potassium nitrate solution. The formation of the chela...