Complexation Properties of Ethylenediaminetetramethylenephosphonic Acid (EDTMP) with Al^III and V^IVO

Abstract

The complexation properties (including stoichiometries and stability constants of the complexes formed) of ethylenediaminetetramethylenephosphonic acid with Al III and V IV O were studied in aqueous solution at an ionic strength of 0.2 M KCl, at 25°C by means of pH potentiometry. For Al III both mononuclear (AlLH n ) and dinuclear (Al 2 LH n ) species were found in solution, whereas for V IV O only mononuclear complexes were detected. For each metal ion, a solid

Coordination abilities of piperyd-1-yl-methane-1,1-diphosphonic acids towards zinc(II), magnesium(II) and calcium(II): Potentiometric and NMR studies

“…Firstly, similar as in the paper of Kiss and co-workers [43] we disregarded the last dissociation process and considered HL 3À species of ligand as L 3À in the formation equilibrium: pM + qHL + rH ¢ M p L q H r+q . The reason for this is an exceptionally high pK 5 value, not detectable from the potentiometric and NMR titration studies.…”

Electrospray mass spectrometry (ESI‐MS) in the study of metal–ligand solution equilibria

“…In the case of complicated systems (i.e., systems involving several complexes, or systems in which polynuclear species are present), potentiometric, spectrophotometric, and calorimetric data may leave some ambiguity in the identification of the correct model. In these cases, supplementary qualitative information can be acquired from NMR (Di Marco et al, 1999) and, less frequently, from other spectroscopic techniques as CD (Daniele, Prenesti, & Ostacoli, 1996), IR (Bombi et al, 1990), and EPR (Di Marco et al, 2004). In the few cases in which suitable crystals are obtained, X-ray diffractometry can indirectly confirm the stoichiometry of one of the species in solution .…”

Surface‐activated chemical ionization versus electrospray ionization in the study of selected aluminium(III)/ligand solution equilibria

“…1) Solutions for the SACI-MS and ESI-MS measurements were prepared by dissolving in water (purified with a Milli-Q/plus apparatus, Millipore) weighed amounts of ligand (1: Aldrich; 2: Ega-Chemie; 3: Baker; 4: product of synthesis 6 ) and AlCl 3 Á 6H 2 O (Fluka). Concentration values are given in molality (m, mol/kg).…”