The binding energies of trialkylgermanium cations to water molecules studied by high pressure mass spectrometry

1987 ◽  
Vol 65 (9) ◽  
pp. 2146-2148 ◽  
Author(s):  
John Alfred Stone ◽  
Wilhelmus Johannes Wytenburg

The binding energies of H2O to R3Ge+ have been measured using pulsed electron beam, high pressure mass spectrometry. van't Hoff plots have yielded thermodynamic data (ΔH0, ΔS0) for the reactions, [5], [Formula: see text]and [7], [Formula: see text]. [Formula: see text] decreases with increasing size of R (CH3 28.6 ± 0.5 kcal mol−1, C4H9 20.6 ± 1.2 kcal mol−1) while [Formula: see text] shows much less change (34.4 ± 0.9 to 30.3 ± 2.8 cal K−1 mol−1). Comparison with data for (CH3)3M+ (M = Si, Sn) shows that binding energy decreases with increasing size of M.

1982 ◽  
Vol 60 (7) ◽  
pp. 910-915 ◽  
Author(s):  
John A. Stone ◽  
Dena E. Splinter ◽  
Soon Yau Kong

Proton transfer equilibria [Formula: see text] and NO+ transfer equilibria [Formula: see text] have been studied for the following bases B, benzene, toluene, o-, m-, and p-xylene. NO+ transfer equilibria for fluoro- and chlorobenzene have also been studied. Pulsed electron beam, high-pressure ion source mass spectrometry has been used to obtain the equilibrium constant K and hence the free energy changes ΔG0 and from van't Hoff plots, ΔH0 and ΔS0. Entropy changes are in general much smaller for NO+ transfer than for H+ transfer but the magnitude of the changes in the proton affinity and NO+ affinity of toluene caused by a fluorine substituent is about the same, even though the absolute value of the proton affinity is greater by a factor of 4. The position of the F substituent on toluene has a marked effect on proton affinity but no effect on NO+ affinity. The latter appears to be responsive only to the inductive effect.


MRS Advances ◽  
2016 ◽  
Vol 1 (6) ◽  
pp. 433-439 ◽  
Author(s):  
Asghar Ali ◽  
Patrick Morrow ◽  
Redhouane Henda ◽  
Ragnar Fagerberg

AbstractThis study reports on the preparation of cobalt doped zinc oxide (Co:ZnO) films via pulsed electron beam ablation (PEBA) from a single target containing 20 w% Co on sapphire (0001) and silicon (100) substrates. The films have been deposited at various temperatures (350оC, 400оC, 450оC) and pulse frequencies (2 Hz, 4 Hz), under a background argon (Ar) pressure of about 3 mtorr, and an accelerating voltage of 14 kV. The surface morphology has been examined by atomic force microscopy (AFM) and scanning electron microscopy (SEM). According to SEM analysis, the films consist of nano-globules whose size is in the range of 80-178 nm. Energy dispersive x-ray spectroscopy (EDX) reveals that deposition is congruent and the prepared films contain ∼20±5 w% cobalt. It has been found that the nano-globules in the deposited films are cobalt-rich zones containing ∼70 w% Co. From x-ray photoelectron spectroscopy (XPS) analysis, Co 2p3/2 peaks indicate that the deposited films contain CoO (binding energy = 780.5 eV) as well as metallic Co (binding energy = 778.1-778.5 eV). X-ray diffraction (XRD) analysis supports the presence of metallic Co hcp phase (2ϴ = 44.47° and 47.43°) in the films.


2014 ◽  
Vol 21 (7) ◽  
pp. 072302 ◽  
Author(s):  
R. V. Sazonov ◽  
G. E. Kholodnaya ◽  
D. V. Ponomarev ◽  
G. E. Remnev

Author(s):  
V. S. Soldatov ◽  
T. V. Bezyazychnaya ◽  
E. G. Kosandrovich

Based on the data of ab initio calculation of the structure of (RSO3)2Mg (H2O)18 and (RSO3Rb)2(H2O)16 clusters, which simulate the structure of swollen sulfostyrene ion exchangers in the corresponding ionic forms and a water cluster of comparable size, the numbers of water molecules directly bound to cations and their coordination numbers, including the oxygen atoms of the sulfonic groups linked to the cation, were calculated. It is shown that the first molecular layer around the magnesium ion is formed from water molecules with the highest binding energy with the cluster, and around the rubidium ion – from the molecules of the nearest environment with the lowest binding energies. This is explained by the fact that the transfer of water molecules from its volume to magnesium hydrate is energetically favorable, but not to rubidium hydrate. Therefore, the magnesium ion builds its hydrate mainly from water molecules with the highest binding energy in order to obtain the greatest energy gain, and the rubidium ion – from molecules with the lowest energy, which provides the smallest energy loss.


1972 ◽  
Vol 50 (14) ◽  
pp. 2230-2235 ◽  
Author(s):  
J. D. Payzant ◽  
A. J. Cunningham ◽  
P. Kebarle

The rate constants for the forward and reverse components of gas phase reactions:[Formula: see text]were measured with a pulsed electron beam, time resolved detection high pressure mass spectrometer at 300 °K. O2, Ar, and He at pressures from 1–7 Torr were used as third gas M. The forward reactions were found to be third order and the reverse reactions second order. Establishment of the equilibria could also be observed.


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