Gas phase multicollisional reactions of metal cluster cations with water molecules

1999 ◽  
Vol 1 (15) ◽  
pp. 3461-3465 ◽  
Author(s):  
Victor A. Mikhailov ◽  
Perdita E. Barran ◽  
Anthony J. Stace
Keyword(s):  
Gas Phase ◽  
Metal Cluster ◽  
Water Molecules

Proof of the Catalytic Activity of a Naked Metal Cluster in the Gas Phase

1992 ◽  
Vol 31 (5) ◽  
pp. 636-638 ◽  
Author(s):  
Patrick Schnabel ◽  
Konrad G. Weil ◽  
Manfred P. Irion
Keyword(s):  
Catalytic Activity ◽  
Gas Phase ◽  
Metal Cluster

scholarly journals Computational Evidence Suggests That 1-chloroethanol May Be an Intermediate in the Thermal Decomposition of 2-chloroethanol into Acetaldehyde and HCl

2019 ◽  
Author(s):  
Zoi Salta ◽  
Agnie M. Kosmas ◽  
Oscar Ventura ◽  
Vincenzo Barone
Keyword(s):  
Aqueous Solution ◽  
Water Molecule ◽  
Gas Phase ◽  
Density Functional ◽  
Water Molecules ◽  
Functional Theory ◽  
Direct Transformation ◽  
The Density Functional Theory ◽  
Successive Step ◽  
The One

<p>The dehalogenation of 2-chloroethanol (2ClEtOH) in gas phase with and without participation of catalytic water molecules has been investigated using methods rooted into the density functional theory. The well-known HCl elimination leading to vinyl alcohol (VA) was compared to the alternative elimination route towards oxirane and shown to be kinetically and thermodynamically more favorable. However, the isomerization of VA to acetaldehyde in the gas phase, in the absence of water, was shown to be kinetically and thermodynamically less favorable than the recombination of VA and HCl to form the isomeric 1-chloroethanol (1ClEtOH) species. This species is more stable than 2ClEtOH by about 6 kcal mol<sup>-1</sup>, and the reaction barrier is 22 kcal mol<sup>-1</sup> vs 55 kcal mol<sup>-1</sup> for the direct transformation of VA to acetaldehyde. In a successive step, 1ClEtOH can decompose directly to acetaldehyde and HCl with a lower barrier (29 kcal mol<sup>-1</sup>) than that of VA to the same products (55 kcal mol<sup>-1</sup>). The calculations were repeated using a single ancillary water molecule (W) in the complexes 2ClEtOH_W and 1ClEtOH_W. The latter adduct is now more stable than 2ClEtOH_W by about 8 kcal mol<sup>-1</sup>, implying that the water molecule increased the already higher stability of 1ClEtOH in the gas phase. However, this catalytic water molecule lowers dramatically the barrier for the interconversion of VA to acetaldehyde (from 55 to 6 kcal mol<sup>-1</sup>). This barrier is now smaller than the one for the conversion to 1ClEtOH (which also decreases, but not so much, from 22 to 12 kcal mol<sup>-1</sup>). Thus, it is concluded that while 1ClEtOH may be a plausible intermediate in the gas phase dehalogenation of 2ClEtOH, it is unlikely that it plays a major role in water complexes (or, by inference, aqueous solution). It is also shown that neither in the gas phase nor in the cluster with one water molecule, the oxirane path is competitive with the VA alcohol path.</p>

Solvation of propanediol ions by water molecules in the gas phase

2004 ◽  
Vol 15 (8) ◽  
pp. 1123-1127 ◽  
Author(s):  
John J. Gilligan ◽  
Nancy E. Vieira ◽  
Alfred L. Yergey
Keyword(s):  
Gas Phase ◽  
Water Molecules

A Comparative Study of the BJH- and MCYL-Type Potentials Applied to the Gaseous Water Dimer

1991 ◽  
Vol 46 (5) ◽  
pp. 426-432
Author(s):  
Zdenek Slanina
Keyword(s):  
Gas Phase ◽  
Minimum Energy ◽  
Water Dimer ◽  
Energy Structure ◽  
Water Molecules ◽  
Constant Matrix ◽  
Force Constant Matrix ◽  
Molecular Force ◽  
Phase Water ◽  
Derivatives Of

AbstractVarious refined potentials describing the intra- and inter-molecular force fields of water molecules arc used to calculate the properties of the gas-phase water dimer. The intra-molecular parts have been taken from spectroscopic or quantum-chemical sources. The minimum energy structure was found iteratively using the first derivatives of the potential; the force-constant matrix was constructed by numerical difierentation. A quite close agreement between the Bopp-Jancso-Heinzinger and the Matsuoka-Clementi-Yoshimine-Lie potentials is found. The treatment is applied to seven observed water-dimer isotopomeric isomerizations

Monomerie Metaphosphate: Does it Exist in Aqueous Solution?

1987 ◽  
Vol 42 (12) ◽  
pp. 1585-1587 ◽  
Author(s):  
R. G. Keesee ◽  
A. W. Castleman
Keyword(s):  
Aqueous Solution ◽  
Gas Phase ◽  
Water Molecules ◽  
The Third ◽  
Enthalpy Changes ◽  
Successive Addition ◽  
Dihydrogen Orthophosphate

AbstractEnthalpy changes for the successive addition of the first four water molecules onto monomeric metaphosphate anion in the gas phase have been determined to be -12.6, -11.4, -16.3, and - 11.0 kcal/mol, respectively. The results suggest that the first addition is a simple formation of the adduct PO3- · H2O as apposed to formation of the dihydrogen orthophosphate anion (HO)2PO2-, but that the third addition involves a transformation to the orthophosphate anion.

Gas-phase electrochemistry: Measuring absolute potentials and investigating ion and electron hydration

2011 ◽  
Vol 83 (12) ◽  
pp. 2129-2151 ◽  
Author(s):  
William A. Donald ◽  
Evan R. Williams
Keyword(s):  
Gas Phase ◽  
Ion Solvation ◽  
Water Molecules ◽  
Hydrogen Electrode ◽  
Half Cell ◽  
Hydration Enthalpy ◽  
A Value ◽  
Hydrated Ions ◽  
Solvation Energies ◽  
The University

In solution, half-cell potentials and ion solvation energies (or enthalpies) are measured relative to other values, thus establishing ladders of thermochemical values that are referenced to the potential of the standard hydrogen electrode (SHE) and the proton hydration energy (or enthalpy), respectively, which are both arbitrarily assigned a value of 0. In this focused review article, we describe three routes for obtaining absolute solution-phase half-cell potentials using ion nanocalorimetry, in which the energy resulting from electron capture (EC) by large hydrated ions in the gas phase are obtained from the number of water molecules lost from the reduced precursor cluster, which was developed by the Williams group at the University of California, Berkeley. Recent ion nanocalorimetry methods for investigating ion and electron hydration and for obtaining the absolute hydration enthalpy of the electron are discussed. From these methods, an absolute electrochemical scale and ion solvation scale can be established from experimental measurements without any models.

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