Thermal intramolecular rearrangement of methyl-1,3,5-cycloheptatrienes in the gas phase. II. Thermodynamic data from equilibrium studies of the positional isomers

1968 ◽  
Vol 90 (1) ◽  
pp. 1-5 ◽  
Author(s):  
Kurt W. Egger
Keyword(s):  
Gas Phase ◽  
Phase Ii ◽  
Thermodynamic Data ◽  
Intramolecular Rearrangement ◽  
Positional Isomers ◽  
Equilibrium Studies

Electron Transfer and Ligand Addition to Atomic Mercury Cations in the Gas Phase:  Kinetic and Equilibrium Studies at 295 K

2006 ◽  
Vol 45 (24) ◽  
pp. 9646-9653 ◽  
Author(s):  
Xiang Zhao ◽  
Eric Flaim ◽  
Lise Huynh ◽  
Michael J. Y. Jarvis ◽  
Ping Cheng ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Gas Phase ◽  
Equilibrium Studies ◽  
Ligand Addition ◽  
Atomic Mercury

Novel Peptide Dissociation:  Gas-Phase Intramolecular Rearrangement of Internal Amino Acid Residues

1997 ◽  
Vol 119 (24) ◽  
pp. 5481-5488 ◽  
Author(s):  
Richard W. Vachet ◽  
Barney M. Bishop ◽  
Bruce W. Erickson ◽  
Gary L. Glish
Keyword(s):  
Amino Acid ◽  
Gas Phase ◽  
Intramolecular Rearrangement ◽  
Amino Acid Residues ◽  
Peptide Dissociation

scholarly journals Nitrogen removal from natural gas: Phase II

1999 ◽  
Author(s):  
D.C. Bomberger ◽  
J.L. Bomben ◽  
A. Amirbahman ◽  
M. Asaro
Keyword(s):  
Natural Gas ◽  
Gas Phase ◽  
Phase Ii ◽  
Nitrogen Removal

Conformational polymorphism in a Schiff-base macrocyclic organic ligand: an experimental and theoretical study

2010 ◽  
Vol 66 (5) ◽  
pp. 527-543 ◽  
Author(s):  
Leonardo Lo Presti ◽  
Raffaella Soave ◽  
Mariangela Longhi ◽  
Emanuele Ortoleva
Keyword(s):  
Schiff Base ◽  
Solid State ◽  
Dft Calculations ◽  
Gas Phase ◽  
Phase Ii ◽  
Density Functional ◽  
Organic Ligand ◽  
Stable Phase ◽  
Stable Form ◽  
Molecular Conformations

Polymorphism in the highly flexible organic Schiff-base macrocycle ligand 3,6,9,17,20,23-hexa-azapentacyclo(23.3.1.111,15.02,6.016,20)triaconta-1(29),9,11,13,15(30),23,25,27-octaene (DIEN, C24H30N6) has been studied by single-crystal X-ray diffraction and both solid-state and gas-phase density functional theory (DFT) calculations. In the literature, only solvated structures of the title compound are known. Two new polymorphs and a new solvated form of DIEN, all obtained from the same solvent with different crystallization conditions, are presented for the first time. They all have P\bar 1 symmetry, with the macrocycle positioned on inversion centres. The two unsolvated polymorphic forms differ in the number of molecules in the asymmetric unit Z′, density and cohesive energy. Theoretical results confirm that the most stable form is (II°), with Z′ = 1.5. Two distinct molecular conformations have been found, named `endo' or `exo' according to the orientation of the imine N atoms, which can be directed towards the interior or the exterior of the macrocycle. The endo arrangement is ubiquitous in the solid state and is shared by two independent molecules which constitute an invariant supramolecular synthon in all the known crystal forms of DIEN. It is also the most stable arrangement in the gas phase. The exo form, on the other hand, appears only in phase (II°), which contains both the conformers. Similarities and differences among the occurring packing motifs, as well as solvent effects, are discussed with the aid of Hirshfeld surface fingerprint plots and correlated to the results of the energy analysis. A possible interconversion path in the gas phase between the endo and the exo conformers has been found by DFT calculations; it consists of a two-step mechanism with activation energies of the order of 30–40 kJ mol−1. These findings have been related to the empirical evidence that the most stable phase (II°) is also the last appearing one, in accordance with Ostwald's rule.

Rearrangement of the Fulminate Anion (CNO-) to the Cyanate Anion (OCN-). Possible Intermediacy of the Oxazirinyl Anion

1986 ◽  
Vol 39 (6) ◽  
pp. 913 ◽  
Author(s):  
WK Li ◽  
J Baker ◽  
L Radom
Keyword(s):  
Gas Phase ◽  
Electron Correlation ◽  
Basis Set ◽  
Intramolecular Rearrangement ◽  
Molecular Orbital Calculations ◽  
Potential Well ◽  
Electron Loss ◽  
Diffuse Function ◽  
Moller Plesset ◽  
High Level

The rearrangement of the fulminate anion (CNO-) to the cyanate anion (OCN-) has been examined by using high-level ab initio molecular orbital calculations which include a diffuse-function-augmented polarization basis set and electron correlation incorporated at the full fourth-order Moller-Plesset level (MP4). The reaction is predicted to be exothermic by 275 kJ mol-1. Our best calculations indicate theinvolvement of a metastable cyclic oxazirinyl anion intermediate. However, this lies in an extremely shallow potential well and, in contrast to the predictions of semiempirical calculations, is unlikely to have more than a fleeting existence. The fulminate and cyanate anions are calculated to be stable with respect to electron loss and stable with respect to intramolecular rearrangement; accordingly, both should be observable gas-phase species.

Continuous manufacturing of a light-textured foamed fresh cheese by dispersion of a gas phase. II. Influence of formulation

2006 ◽  
Vol 77 (1) ◽  
pp. 14-26 ◽  
Author(s):  
Ch. Vial ◽  
Rajeev K. Thakur ◽  
A. Pérez Quintáns ◽  
G. Djelveh ◽  
L. Picgirard
Keyword(s):  
Gas Phase ◽  
Phase Ii ◽  
Continuous Manufacturing ◽  
Fresh Cheese
Sign in / Sign up

Export Citation Format

Share Document