scholarly journals The Gas-Phase Heats of Formation ofn-Alkanes as a Function of the Electrostatic Potential Extrema on their Molecular Surfaces

2004 ◽  
Vol 1 (2) ◽  
pp. 81-86 ◽  
Author(s):  
Fakhr M. Abu-Awwad
Keyword(s):  
Gas Phase ◽  
Electrostatic Potential ◽  
Density Functional ◽  
Absolute Error ◽  
Heat Of Formation ◽  
Molecular Surface ◽  
Heats Of Formation ◽  
Normal Alkanes ◽  
Surface Electrostatic Potential ◽  
Hybrid Density Functional

The hybrid density functional B3LYP is employed to map the molecular electrostatic potentials on the surfaces of twenty normal alkanes, (CnH2n+2), n = 1-20. It is shown that gas-phase heats of formation of the alkanes can be represented quantitatively in terms of the potential, where a general equation of the heat of formation is introduced as a function of potentials' extrema, VS,minand VS,maxwith average absolute error of 0.028 kcal/mol and a standard deviation of 0.048 kcal/mol. This should be viewed as a success of the B3LYP functional and the molecular surface electrostatic potential as tools of chemistry. The predicted gas-phase heats of formation of thirty normal alkanes (n = 21-50) are reproduced and compared to their experimental counterparts when available.

Methyl-2-methyl-2-(4-methyl-phenyl)sulfonamido propanoate: structural study, supramolecular architecture and analysis of molecular surface electrostatic potential

2016 ◽  
Vol 231 (9) ◽  
Author(s):  
Paramita Chatterjee ◽  
Tanusri Dey ◽  
Uday Das ◽  
Vommina V. Sureshbabu ◽  
Alok K. Mukherjee
Keyword(s):  
Structural Study ◽  
Electrostatic Potential ◽  
Molecular Surface ◽  
Supramolecular Architecture ◽  
Surface Electrostatic Potential ◽  
Methyl Phenyl

AbstractAn arylsulfonamide compound, methyl-2-methyl-2-(4-methylphenyl)sulfonamido propanoate, (

Computational Determination of Heats of Formation of Energetic Compounds

1995 ◽  
Vol 418 ◽  
Author(s):  
Peter Politzer ◽  
Jane S. Murray ◽  
M. Edward Grice
Keyword(s):  
Gas Phase ◽  
Density Functional ◽  
Functional Group ◽  
Solid Phase ◽  
Heats Of Formation ◽  
Energetic Compounds ◽  
Phase Data ◽  
Heats Of Vaporization ◽  
Group Effects

AbstractA recently-developed density functional procedure for computing gas phase heats of formation is briefly described and results for several categories of energetic compounds are summarized and discussed. Liquid and solid phase values can be obtained by combining the gas phase data with heats of vaporization and sublimation estimated by means of other relationships. Some observed functional group effects upon heats of formation are noted.

A computational study of the SNAr reaction of 2-ethoxy-3,5-dinitropyridine and 2-methoxy-3,5-dinitropyridine with piperidine

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Oluwakemi A. Oloba-Whenu ◽  
Idris O. Junaid ◽  
Chukwuemeka Isanbor
Keyword(s):  
Hydrogen Bonding ◽  
Gas Phase ◽  
Density Functional ◽  
Computational Study ◽  
Density Functional Theory Method ◽  
Basis Set ◽  
Slow Step ◽  
Functional Theory ◽  
Snar Reaction ◽  
Hybrid Density Functional

AbstractA computational study of the chemical kinetics and thermodynamics study of the SNAr between 3,5-dinitroethoxypyridine 1a and 3,5-dinitromethoxypyridine 1b with piperidine 2 in the gas phase is reported using hybrid density functional theory method B3PW91 and 6–31G(d,p) basis set. The reaction was modeled via both the catalyzed and base-catalyzed pathways which proceeded with the initial attack of the nucleophile 2 on the substrates 1 to yield the Meisenheimer complex intermediate that is stabilized with hydrogen bonding. Calculations show that the reaction goes via the formation and decomposition of a Meisenheimer complex, which was observed to be stabilized by hydrogen bonding. Along the uncatalyzed pathway, the decomposition of the Meisenheimer complex was the slow step and requires about 28 kcal/mol. This barrier was reduced to about 14.8 kcal/mol with the intervention of the base catalyst, thus making the formation of the Meisenheimer complex rate determining. All reactions were calculated to be exothermic, about −6.5 kcal/mol and −0.6 kcal/mol, respectively, for the reaction of 1a and 1b with 2.

scholarly journals Chelate Coordination Compounds as a New Class of High-Energy Materials: The Case of Nitro-Bis(Acetylacetonato) Complexes

Molecules ◽  
2021 ◽  
Vol 26 (18) ◽  
pp. 5438
Author(s):  
Danijela S. Kretić ◽  
Ivana S. Veljković ◽  
Aleksandra B. Đunović ◽  
Dušan Ž. Veljković
Keyword(s):  
Electrostatic Potential ◽  
High Performance ◽  
Density Functional ◽  
High Efficiency ◽  
High Energy ◽  
Molecular Surface ◽  
Energy Materials ◽  
Dissociation Energies ◽  
Central Regions ◽  
And Performance

The existence of areas of strongly positive electrostatic potential in the central regions of the molecular surface of high-energy molecules is a strong indicator that these compounds are very sensitive towards detonation. Development of high-energy compounds with reduced sensitivity towards detonation and high efficiency is hard to achieve since the energetic molecules with high performance are usually very sensitive. Here we used Density Functional Theory (DFT) calculations to study a series of bis(acetylacetonato) and nitro-bis(acetylacetonato) complexes and to elucidate their potential application as energy compounds with moderate sensitivities. We calculated electrostatic potential maps for these molecules and analyzed values of positive potential in the central portions of molecular surfaces in the context of their sensitivity towards detonation. Results of the analysis of the electrostatic potential demonstrated that nitro-bis(acetylacetonato) complexes of Cu and Zn have similar values of electrostatic potential in the central regions (25.25 and 25.06 kcal/mol, respectively) as conventional explosives like TNT (23.76 kcal/mol). Results of analysis of electrostatic potentials and bond dissociation energies for the C-NO2 bond indicate that nitro-bis(acetylacetonato) complexes could be used as potential energetic compounds with satisfactory sensitivity and performance.

Sign in / Sign up

Export Citation Format

Share Document