Inorganic metal cations

The reactivity of the transition metal ions depends on the availability of an orbital and the gain in energy on addition of the electron. Rate coefficients for the reaction of some dispositive ions are shown in Table 3. 

The initial products of the reactions of hydrated electrons with bivalent transition metal ions are the univalent ions. 

These have been identified by their transient ultraviolet absorption spectra 

Copper is exceptional in that its monovalent cation is relatively stable. The production of unusual oxidation states in this way may lead to the use of the hydrated electron in inorganic synthesis. 

The silver ion is reduced to Ag°, which has been detected spectro-ph otometrically [41]. 

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A. Weston, P. Brown, E Jandik, W. R. Jones and A. L. Heckenberg, Factors affecting the separation of inorganic metal cations by capillary electrophoresis, /. Chromatogr.. 593,289,1992. 

Yes there are, and wouldn t you know it, these are, in essence, SPE-type methods Both cation- and anion-exchange resins have been used to preconcentrate inorganic metal cations while removing anionic interferents. A large body of work has been related to the formation of the polychloro... 

Adsorption of Metal Ions and Ligands. The sohd—solution interface is of greatest importance in regulating the concentration of aquatic solutes and pollutants. Suspended inorganic and organic particles and biomass, sediments, soils, and minerals, eg, in aquifers and infiltration systems, act as adsorbents. The reactions occurring at interfaces can be described with the help of surface-chemical theories (surface complex formation) (25). The adsorption of polar substances, eg, metal cations, M, anions. A, and weak acids, HA, on hydrous oxide, clay, or organically coated surfaces may be described in terms of surface-coordination reactions ... 

Alcohols react with boric acid with elimination of water to form borate esters, B(OR)3. A wide variety of borate salts and complexes have been prepared by the reaction of boric acid and inorganic bases, amines, and heavy-metal cations or oxyanions (44,45). Fusion with metal oxides yields... 

Chemical pretreatment is often used to improve the performance of contaminant removal. The use of chemical flocculants is based on system efficiency, the specific DAF application and cost. Commonly used chemicals include trivalent metallic salts of iron, such as FeClj or FeSO or aluminum, such as AISO. Organic and inorganic polymers (cationic or anionic) are generally used to enhance the DAF process. 

Ionophores constitute a large collection of structurally diverse substances that share the ability to complex cations and to assist in the translocation of cations through a lipophilic interface.1 Using numerous Lewis-basic heteroatoms, an ionophore organizes itself around a cationic species such as an inorganic metal ion. This arrangement maximizes favorable ion-dipole interactions, while simultaneously exposing a relatively hydrophobic (lipophilic) exterior. 

The sites for complex formation in DMSO with inorganic salts depend remarkably on the nature of the metals involved in the salts. The alkali or alkali earth metallic salts form a complex with the oxygen atom in DMSO while Pd(II) or Pt(II) associates strongly at the sulphur atom. The IR frequency of the S—O bond of DMSO shifts to even lower wave numbers when associated with such metal cations as Li+, Na+ or Ca+ +34. On the other hand, in the case of Pd(II) or Pt(II), the S—O frequency appears at higher wave numbers, at around llOO-llAOcm 135. These different shifts for the S—O frequency afford a convenient diagnosis to determine whether the cation associates with the oxygen or the sulphur atom in DMSO. 

J.-J. Xu, H.-Q. Fang, and H.-Y. Chen, The electrochemical characteristics of an inorganic monolayer film modified gold electrode and its molecular recognition of alkali metal cation. J. Electroanal. Chem. 426,139-143 (1997). 

The chelate effect in inorganic chemistry is the ability of two or more covalently linked metal ligands (eg., thiols, amines, carboxylates, etc) to bind a metal cation much more strongly than the individual (unlinked) metal ligands (Fig. 8). This phe-... 

Bare metal cations can be prepared from almost any inorganic source as long as enough energy is given to the sample to allow dissociation, vaporization, and ionization. Metal anions are less well studied due to the low electron affinities of most transition metals. Where M+ and M ions are compared, the M ions are generally less reactive. 

Supramolecular architectures in which transition metal cationic centres are linked via hydrogen-bonded supramolecular synthons [1,2] comprise an increasingly important class of inorganic co-ordination polymers [3], owing to their multi-dimensional, multi-functional network structures. 

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