The Enthalpies of Formation for Polychlorinated Dibenzofurans with Use of G3XMP2 Model Chemistry and Density Functional Theory

2009 ◽  
Vol 113 (1) ◽  
pp. 238-245 ◽  
Author(s):  
Liming Wang ◽  
Yi-Liang He
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Enthalpies Of Formation ◽  
Polychlorinated Dibenzofurans ◽  
Functional Theory

Enthalpies of Formation of Dibenzo-p-dioxin and Polychlorinated Dibenzo-p-dioxins Calculated by Density Functional Theory

2003 ◽  
Vol 107 (16) ◽  
pp. 2848-2854 ◽  
Author(s):  
Olga V. Dorofeeva ◽  
Vladimir S. Yungman
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Enthalpies Of Formation ◽  
Functional Theory

scholarly journals Predicting density functional theory total energies and enthalpies of formation of metal-nonmetal compounds by linear regression

2016 ◽  
Vol 93 (8) ◽  
Author(s):  
Ann M. Deml ◽  
Ryan O’Hayre ◽  
Chris Wolverton ◽  
Vladan Stevanović
Keyword(s):  
Density Functional Theory ◽  
Linear Regression ◽  
Density Functional ◽  
Enthalpies Of Formation ◽  
Functional Theory ◽  
Total Energies

DIRECT DENSITY FUNCTIONAL THEORY DYNAMICS STUDY FOR THE CH3OCF2CF2OCH3 + OH REACTION

2011 ◽  
Vol 10 (02) ◽  
pp. 231-244 ◽  
Author(s):  
HONG-BO YU ◽  
FENG-CHAO CUI ◽  
YONG-XIA WANG ◽  
HONG-XIA LIU ◽  
JING-YAO LIU
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Theoretical Data ◽  
State Theory ◽  
Stationary Points ◽  
Enthalpies Of Formation ◽  
Oh Radicals ◽  
Isodesmic Reactions ◽  
Functional Theory ◽  
Barrier Heights

The mechanism and kinetics of the reaction of CH3OCF2CF2OCH3 with OH radicals have been studied theoretically by a direct density functional theory dynamics method. All possible H -abstraction channels and displacement processes taking place on two different conformers of CH3OCF2CF2OCH3 have been taken into consideration. The potential energy surface information including the optimized geometries and harmonic vibrational frequencies of all the stationary points and barrier heights involved in these channels were obtained at the BB1K/6-31+G(d,p) level of theory. The rate constants were calculated using improved canonical variational transition state theory (ICVT) with the small-curvature tunneling correction (SCT) over the temperature range of 200–2000 K. The overall rate constant for the title reaction, which was obtained by considering the weight factor of each conformer from the Boltzman distribution function, is in reasonable agreement with the available experimental value. Three-term Arrhenius expression is fitted to be k T = 1.56 × 10-20 T 2.47 exp (-124.64/ T ) cm 3 molecule-1 s-1 (200–2000 K). Also, the enthalpies of formation of the reactant CH3OCF2CF2OCH3 and product radicals CH3OCF2CF2OCH2 and CH3OCF2CF2O , which lack experimental or theoretical data, were evaluated via applying isodesmic reactions.

scholarly journals A Framework for Quantifying Uncertainty in DFT Energy Corrections

2021 ◽  
Author(s):  
Amanda Wang ◽  
Ryan Kingsbury ◽  
Matthew McDermott ◽  
Matthew Horton ◽  
Anubhav Jain ◽  
...  
Keyword(s):  
Phase Diagram ◽  
Density Functional Theory ◽  
Density Functional ◽  
Enthalpies Of Formation ◽  
Functional Theory ◽  
Chemical Systems ◽  
Correction Scheme ◽  
Derived Properties ◽  
Quantifying Uncertainty ◽  
Formation Phase

In this work, we demonstrate a method to quantify uncertainty in corrections to density functional theory (DFT) energies based on empirical results. Such corrections are commonly used to improve the accuracy of computational enthalpies of formation, phase stability predictions, and other energy-derived properties, for example. We incorporate this method into a new DFT energy correction scheme comprising a mixture of oxidation-state and composition-dependent corrections and show that many chemical systems contain unstable polymorphs that may actually be predicted stable when uncertainty is taken into account. We then illustrate how these uncertainties can be used to estimate the probability that a compound is stable on a compositional phase diagram, thus enabling better-informed assessments of compound stability.

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