Citrato complexes

Ca", although forming less stable complexes with citrate than Cu and Zn ", outcompetes these ions in forming citrato complexes, because it is present in much higher concentration than Cu(II) and Zn(II). 

Citrato complexes. Abbreviations cit = citrate lac = lactate. For structurally characterised complexes, see ref. 24. The charges of the complexes vary with pH. 

Structures for vanadyl complexes of citric acid.P l The formulae for the citrato complexes [(VO)2(Hcit)(H2cit)] and [(VO)2(Hcit)2] have been modified to account for the deprotonation grade of the coordinated citrate. Note, in the structurally characterised complex [(VO)2(cit)(Hcit)] , the differing coordination modes of the two Hcit. ... 

Formation ofYBaCnO oxocarbonate intermediate. Physica C 1993 218 429-436 Grigor eva V.V., Golnbeva I.V. Niobium(V) citrato-complexes. Rus. J. Inorg. Chem. 1975 20 526-529... 

The Pu +/Pu + couple for a series of Pu(IV)/(EDTA ) based complexes, where EDTA = ethylenediaminetetraacetate, has been studied as a function of pH and EDTA concentration [118]. The voltammetry was also studied with citrate and carbonate ions present in solution. At a relatively low pH of 2.3 and equimolar Pu +/EDTA concentrations a quasi-reversible one-electron reduction is observed for Pu(EDTA) at E /2 = 0.342 V versus SHE. The quasireversibility of this process remains as the pH is raised to 4.6. Additional voltammetry studies are discussed in the paper for the higher coordinate Pu + species, Pu(EDTA)-L (where L = EDTA, carbonate, citrato), all of which show irreversible electron-transfer behavior. 

Tellurium(IV) sulfato complexes of composition 2(2Te02 S03),MHS04-2H20 have been reported,46 from which the anhydrous compounds were obtained by calcination. Carboxylic acids have also been found to form anionic complexes with tellurium(IV) and polonium(IV). For example, the silver salts of the citrato- and tartrato-tellurates(IV) have been described47 as insoluble in water but soluble in nitric acid. 

The citrato peroxo complex is formed in situ from equimolar NaV03 and H202 with two mole-equivalents of citric acid. The IDA complex is formed analogously. 

Obviously the citrato and the EDTA complexes of Fe(II) are sufficiently strong reductants for iodine. 

Narendar Y., Messing G.L. Synthesis, Decomposition and crystallization characteristics ofperoxo-citrato-niobium An aqueous niobium precursor. Chem. Mater. 1997 9 580-587 Nguyen M.H., Lee S.J., Kriven W.M. Synthesis of oxide powders hy way of a pol5mieric steric entrapment precursor route. J. Mater. Res. 1999 14 3417-3426 Ogihara T., Azuma Y., Katayama K. Synthesis and electrochemical property of LiMn02 precursor by complexed polymerized method. J. Ceram. Soc. Jpn. 1999 107 465-468 Pearce K.N. Formation constants for magnesium and calcium citrate complexes. Aust. J. Chem. 1980 33 1511-1517... 

Cawich CM, Ibrahim A, Link KL, Bumgartner A, Patro MD, Mahapatro SN, Lay PA, Levina A, Eaton SS, Eaton GR. 2003. Synthesis of a pyridinium bis[citrato(2-)]oxochromate(V) complex and its ligand-exchange reactions. Inorg Chem 42(20) ... 

A novel study on the speciation of aluminum in solution has been reported recently by Bertsch et al. [73]. Fluoro, oxalato, and citrato aluminum complexes were identified as distinct peaks together with free Al(III). Post-column reactionAJV detection was used. These studies were used in kinetic, ion exchange, and toxicological investigations. 

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