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Homopolyatomic cations structure

Although it had been known since the early 19th century that elemental sulfur, selenium and tellurium dissolve in oleum to afford intensively colored solutions, it was not until the 1960s that the structures of the responsible homopolyatomic cations began to be elucidated in detail. [Pg.232]

Direct Synthesis reaction of, 6 395 fluoride, 21 235, 237, 239, 249 homopolyatomic cations, 17 82 ion, stereochemistry, 2 40-41, 44-45 isocyanates, preparation, 9 158 properties, 9 157 isothiocyanates, properties, 9 177 mixed valence compounds of, 10 375-381 crystal structure of, 10 376 diffuse reflectance spectrum of, 10 380 structure of Pb," ion, 10 381 nuclear magnetic shielding, 22 224 organometallic compounds, 2 82, 88, 89 oxide, neutron diffraction studies on, 8 231-233... [Pg.162]

Figures 16.8.2(h), (i), and (j) show the structures of Se2J, Se2+, and Se, respectively. They all consist of seven- or eight-membered rings connected by short chains. Each homopolyatomic cation has two three-coordinate atoms that formally carry the positive charges. Se2g has a bicyclo[2.2.4]decane geometry. The Se-Se bond distances vary between 225 and 240 pm, and the Se-Se-Se angles range from 97° to 106°. Se2+ and Se2+ comprise a pair of seven-membered rings connected by a three- and four-atom chain, respectively. Figures 16.8.2(h), (i), and (j) show the structures of Se2J, Se2+, and Se, respectively. They all consist of seven- or eight-membered rings connected by short chains. Each homopolyatomic cation has two three-coordinate atoms that formally carry the positive charges. Se2g has a bicyclo[2.2.4]decane geometry. The Se-Se bond distances vary between 225 and 240 pm, and the Se-Se-Se angles range from 97° to 106°. Se2+ and Se2+ comprise a pair of seven-membered rings connected by a three- and four-atom chain, respectively.
Salts of homopolyatomic cationic clusters now constitute a well-established class of compound— there are at least twenty-six fairly well-characterized examples. It is probable that many other elements will also be shown to form polyatomic cations. As yet reactions of these species have been little studied, and there is obviously a wide open field here awaiting exploration. Many structures of known cations, as well as those that have not yet been prepared, remain to be investigated, and there is a need for theories that can predict the stability and geometry of these cations and provide a description of the bonding. [Pg.82]

Cameron TS, Decken A, Fang M, Ptirsons S, Passmore J, Wood DJ (1999) Oxidation of methyl groups in the reaction of sulfur homopolyatomic cations with acetonitrile formation and crystal structure of the novel trithietanyUum ring. Chem Comm 1801-1802... [Pg.413]

N. Burford, j. Passmore and J. C. P. Sanders, Chap. 2, Preparation, Structure and Energetics of the Homopoly-atomic Cations of Groups 16 and 17, in J. F. Liebman and A. Greenburg (eds.). From Atoms to Polymers Isoelec-tronic Analogies, VCH PubL, Honda, 1989, pp. 53-108. J. Passmore, Chap. 19 Homopolyatomic Selenium Cations... [Pg.759]

The structures of the following homopolyatomic halogen cations have been determined by X-ray analysis ... [Pg.656]

Since these homopolyatomic ZiniD anions and cations are devoid of ligands, they are sometimes referred to as naked" clusters. In general there is a good correlation between electronic structure and geometry as predicted by Wade s rules for the.se clusters, though some exceptions are known. Thus whereas Sn " and Bi are isoelectronic. they have different structures, the latter violating the rules. Only a small distortion of the bismuth cation, however, would convert it to the geometry ob.served for the tin cluster. [Pg.932]

The [N5]+ cation was first predicted to possess a planar V-shaped C2v structure on the basis of quantum chemical calculations. In the most recent experimental study, the [Ns]+ cation was investigated by means of nmr, vibrational (IR, Raman) spectroscopy, and X-ray crystallography. The structural parameters for the three well-characterized homopolyatomic nitrogen species are given in Table II. [Pg.170]


See other pages where Homopolyatomic cations structure is mentioned: [Pg.210]    [Pg.231]    [Pg.243]    [Pg.35]    [Pg.135]    [Pg.145]    [Pg.175]    [Pg.103]    [Pg.445]    [Pg.50]    [Pg.141]    [Pg.103]    [Pg.20]    [Pg.217]    [Pg.225]    [Pg.230]    [Pg.100]    [Pg.547]    [Pg.4787]    [Pg.135]    [Pg.139]    [Pg.4786]    [Pg.817]   
See also in sourсe #XX -- [ Pg.17 , Pg.65 , Pg.66 ]




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