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Gas cations

For quantitative analysis, the resolution of the spectral analyzer must be significantly narrower than the absorption lines, which are - 0.002 nm at 400 nm for Af = 50 amu at 2500°C (eq. 4). This is unachievable with most spectrophotometers. Instead, narrow-line sources specific for each element are employed. These are usually hoUow-cathode lamps, in which a cylindrical cathode composed of (or lined with) the element of interest is bombarded with inert gas cations produced in a discharge. Atoms sputtered from the cathode are excited by coUisions in the lamp atmosphere and then decay, emitting very narrow characteristic lines. More recendy semiconductor diode arrays have been used for AAS (168) (see Semiconductors). [Pg.317]

Molar volume of hypothetical molten salt, cm3/mol Contribution of gas, cation, and anion, respectively, to a salting-out coefficient... [Pg.132]

SiH3+ ions are easily formed in the reactions of noble gas cations and other small ions with SiFLt via dissociative charge transfer (equation l)11. [Pg.1107]

The review of Selig and Holloway [230] on noble-gas cations and anions and the general reviews of Holloway [231] and that of Schrobilgen and Whalen [232] on noble-gas compounds should also be consulted. [Pg.143]

In addition to UV/visible flash photolysis and TRIR spectroscopy, other techniques have been used for the detection of transition metal-noble gas interactions in the gas phase. The interaction of noble gases with transition metal ions has been studied in detail. A series of cationic dimeric species, ML" " (M = V, Cr, Fe, Co, Ni L = Ar, Kr, or Xe), have been detected by mass-spectroscopic methods (55-58). It should be noted that noble gas cations L+ are isoelectronic with halogen atoms, therefore, this series of complexes is not entirely unexpected. The bond dissociation energies of these unstable complexes (Table IV) were determined either from the observed diabatic dissociation thresholds obtained from their visible photodissociation spectra or from the threshold energy for collision-induced dissociation. The bond energies are found to increase linearly with the polarizability of the noble gas. [Pg.133]

Only one set of the MP2 level calculations is shown. Several other gold-noble gas cations were calculated in this study. [Pg.143]

Ga MAS NMR, used to characterize MFI-type gallosilicalite and galloaluminosilicate, has confirmed that the Ga cations are located in the zeolite framework. Quantitative MAS NMR results have suggested that the incorporation of the Ga " cations is seriously inhibited by that of the Al cations if they existed together, while the reverse process is not observed. [Pg.271]

Table 2. Dissociation energies D of diatomic noble gas cations NgNg (in kcal/mol)... Table 2. Dissociation energies D of diatomic noble gas cations NgNg (in kcal/mol)...
The principle of donor-acceptor interactions in noble gas cations is further exemplified by the theoretical study of Radom and coworkers [95a,c] on the series He C" . Figure 12 shows the optimized geometries for the four cations. The intriguing result of the theoretical studies is the rather short He,C bond length for the triply and quadruply charged species HejC and He4C . The latter molecule, which is isoelectronic with methane CH4, has also been calculated by Schleyer [90d]. and are explosive molecules with... [Pg.57]

The conversion of propene to aromatics over borosilicates in the H-, Ga-, and Zn-forms was reported at the 7th International Zeolite Conference by Ono (52). The hydrogen form of the borosilicate exhibited low activity. n the aromatization of propene, producing mainly butenes and C5 (nonaromatic). The Zn exchanged borosilicate exhibited good conversion, with about half of the products being aromatic. The mechanism proposed was bifunctional, with Zn or Ga cations being responsible for the dehydrogenation of olefins. [Pg.538]

Very stable dihalides of the Group 3A(13) metals are known. What is the apparent oxidation state of Ga in GaCl2 Given that GaCE consists of a Ga cation and a GaCU anion, what are the actual oxidation states of Ga Draw the shape of the... [Pg.454]

It is believed that the Fe " " and Ga " cations are randomised on the octahedral sites, with gallium showing a preference for the Ga(ii) site. Magnetic ordering at low temperature allows site populations to be estimated approximately [102, 103]. The spins are oriented close to the c axis [104], and neutron diffraction data show antiparallel sublattices, Fe(i) + Ga(i) and Fe(ii) + Ga(ii) [103]. [Pg.271]

PH+ ions were obtained by the gas-phase reactions of PH3 with rare gas cations and COJ ions [6]. [Pg.34]

Herron, W.J. Goeringer, D.E. McLuckey, S.A. Gas-phase electron-transfer reactions from multiply-charged anions to rare-gas cations. J. Am. Chem. Soc. 1995,117,11555-11562. [Pg.32]


See other pages where Gas cations is mentioned: [Pg.410]    [Pg.411]    [Pg.436]    [Pg.169]    [Pg.232]    [Pg.127]    [Pg.127]    [Pg.137]    [Pg.312]    [Pg.138]    [Pg.397]    [Pg.398]    [Pg.423]    [Pg.1389]    [Pg.1389]    [Pg.283]    [Pg.53]    [Pg.40]    [Pg.265]    [Pg.55]    [Pg.1388]    [Pg.1388]    [Pg.129]    [Pg.1966]    [Pg.1966]    [Pg.1976]    [Pg.2151]    [Pg.89]    [Pg.68]   
See also in sourсe #XX -- [ Pg.114 , Pg.203 , Pg.207 ]




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