Polyatomic inorganic anions

Characteristic frequencies for polyatomic inorganic anions are summarized in Table I for the most important anions. A more general summary in graphic form appears in Fig. 1 [ ]. A recent book also presents structure-spectra data for many inorganic compounds [ ]. 

Characteristic Absorption Frequencies for Several Polyatomic Inorganic Anions in the Sodium Chloride and Cesium Bromide Regions... 

Most polyatomic inorganic ions are anions S04 , COs , NO3, etc. This is the very group for which there are not other good chemical or instrumental methods for identification. Thus IR spectroscopy fills a... 

See Secs. 3.1.2.2 and 3.1.2.8 for naming monatomic and certain polyatomic anions. When an organic group occurs in an inorganic compound, organic nomenclature (q.v.) is followed to name the organic part. 

Pu(IV) forms polyatomic complexes with inorganic and organic ligands. As the number of anionic ligands increases, cationic, neutral, and anionic complexes form and the sequential stabiUty constants, typically decrease. For the following reaction, where M is Pu + and L is a ligand,... 

General suffix for many polyatomic anions in inorganic nomenclature (including coordination nomenclature) and in organic nomenclature nitrate, acetate, hexacyanoferrate. 

Since the time of Berzelius, there has been a persistent argument used by inorganic chemists that, in many cases, valency as a positive integer should be replaced by negative and positive oxidation numbers adding up to zero in a molecule or solid, and to the ionic charge of a polyatomic cation or anion [9]. The same year, 1916, as the Lewis paradigm was formulated [13,14], emphasiz-... 

Now we look briefly at the discriminating character of the chosen Raman signature of polyatomic anions. So, this line should occur at a frequency different from Raman signal arising from other substances. For the most frequent inorganic salts in aqueous solutions, it is demonstrated in Figs. 5, 6... 

The most extensive use of multibody potentials for the simulation of materials by means of ionic pair potentials has been the addition of bond angle bending terms to two-body potentials used to describe silicate and framework structured materials. - s jn addition, harmonic planarity restraining terms have been employed in the simulation of polyatomic anions (in, e.g., inorganic carbonates). Here, as in the organic molecular mechanics methodology described latei structural distortions about an expected geometry are realized at an enei etic cost. 

Inorganic compounds are also formed from more than three elements (see Table 6.8). In these cases, one or more of the ions is often a polyatomic ion. Once you have learned to recognize the polyatomic ions, naming these compounds follows the patterns we have already learned. First identify the ions. Name the cations in the order given, and follow them with the names of the anions. Study the following examples ... 

It must be emphasized, however, that the frequencies listed in various inorganic structure-spectra correlation charts are for the ionic salts. There are many instances in which the polyatomic anion (c.., NO3, SO4 , col , IO3) becomes coordinated to the cation, and this causes a lowering of the symmetry of the anion. These are anions that have double or triple degenerate vibrations. This is reflected in the infrared spectrum by additional absorptions because of the removal of the degeneracy. Many examples of this are illustrated in the transition-metal complexes involving the above anions [ ]. 

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