Application of quantum calculations in the chemical industry—An overview

Deglmann, Peter; Schäfer, Ansgar; Lennartz, Christian

doi:10.1002/qua.24811

Cited by 92 publications

(69 citation statements)

References 230 publications

(253 reference statements)

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“…At present, software for quantum chemical calculations is widely-accepted methods for many branches of chemical research [28] and provides the adequacy and high accuracy for the chemical reactions.…”

Section: Thermodynamic Study Of Catalytic Cracking Reactions Using Qumentioning

confidence: 99%

Mathematical modelling of catalytic cracking riser reactor

Иванчина

Ivashkina

Nazarova

2017

Chemical Engineering Journal

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Section: Thermodynamic Study Of Catalytic Cracking Reactions Using Qumentioning

confidence: 99%

Mathematical modelling of catalytic cracking riser reactor

Иванчина

Ivashkina

Nazarova

2017

Chemical Engineering Journal

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“…73 Thus, accurate prediction on solvent effects remain an important goal and can be very useful in the future studies of the design of best solvent for diverse chemical reactions of practical interest. 74 …”

Section: Resultsmentioning

confidence: 99%

How Accurate is the SMD Model for Predicting Free Energy Barriers for Nucleophilic Substitution Reactions in Polar Protic and Dipolar Aprotic Solvents?

Miguel¹,

Santos²,

Silva³

et al. 2016

Journal of the Brazilian Chemical Society

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In the past seven years, the SMD (Solvent Model Density) method has been widely used by computational chemists. Thus, assessment on the reliability of this model for modeling chemical process in solution is worthwhile. In this report, it was investigated six anion-molecule nucleophilic substitution reactions in methanol and dipolar aprotic solvents. Geometry optimizations have been done at SMD/X3LYP level and single point energy calculations at CCSD(T)/TZVPP + diff level. Our results have indicated that the SMD model is not adequate for dipolar aprotic solvents, with a root of mean squared (RMS) error of 5.6 kcal mol . The classical protic to dipolar aprotic solvent rate acceleration effect was not predicted by the SMD model for the tested systems.Keywords: continuum solvation model, ion solvation, solvent effect, aromatic nucleophilic substitution, M11 functional IntroductionIn the middle of the twentieth century, several experimental studies have led to foundation of empirical rules for qualitative prediction of solvent effects on chemical reactions, authoritatively reviewed by Parker 1 in a classical paper. Nevertheless, a deeper view on solvent effects was only possible with experimental studies of gas phase ion-molecule reactions [2][3][4][5][6] and theoretical modeling of these processes. [7][8][9] It was evident from theoretical studies that solute-solvent interactions can be very strong and produce a profound effect on chemical reactivity. [10][11][12][13][14][15][16][17] On the other hand, gas phase dynamic of chemical reactions can open new mechanistic possibilities. 18,19 Among the different solvents used to conduct ionic chemical reactions, polar protic and dipolar aprotic solvents are paramount due to their property of solubilize ionic species. 20 Methanol is a polar protic solvent and its ability to solvate ions is similar to water. 21,22 In addition, it has the advantage of solubilize many organic molecules not soluble in water. Some usual dipolar aprotic solvents are dimethyl sulfoxide (DMSO), dimethylformamide (DMF) and acetonitrile. Because anions are less solvated in these solvents, anion-molecule reactions are accelerated when transferred from protic to dipolar aprotic solvents. Our ability to describe theoretically this effect is an important goal and a challenge for continuum solvation models once requires these models be able to describe specific solutesolvent interactions. 23 Considering that the Born formula for solvation of a spherical ion of charge q and radius R into a solvent with dielectric constant ε is given by:(1) it could be noted that the use of the same "molecular cavity" for an ionic solute into a protic and dipolar aprotic solvent with high dielectric constant would lead to very similar solvation free energy of ions. A possibility to overcome this problem would be to use different molecular cavity for protic and dipolar aprotic solvents. This approach has reached some successful ten years ago using the polarizable continuum model (PCM) in the study of anion-molecule reaction...

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“…The accuracy of the computational approaches to generate reliable thermodynamic data for industrial process engineering is not fully exploited yet and requires careful inspection. 19 In previous studies for other alkane and alkene isomers 27,58 DFT calculations were not able to reproduce the energetic ordering of the isomers. When comparing to experiment, the MUE for all methods is below 3 kJ mol À1 .…”

Section: Discussionmentioning

confidence: 99%

“…19 Thermochemical predictions are of crucial importance for the design and control of industrial chemical processes. There are accurate composite approaches which include the Gn methodologies 20 23 There is large number of publications that demonstrate that B3LYP and other popular exchange-correlation functionals tend to have significantly larger errors for larger structures (in particular hydrocarbons).…”

Section: Introductionmentioning

confidence: 99%

The thermochemistry of long chain olefin isomers during hydroformylation

Kohls

Stein

2017

New J. Chem.

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Rhodium-catalysed hydroformylation is the major industrial process to obtain aldehyde products from olefins. The isomerization of the olefin at the catalyst is the most prominent side reaction and lowers the overall yield of the process. We here investigate whether the olefin isomer distribution obtained from batch experiments using Rh(BiPhePhos) as a catalyst and n-decene as the olefin reaches the thermodynamic equilibrium and computational quantum chemical approaches are able to accurately reproduce the experimental olefin isomer distribution. The relative energies of cis/trans configurational and double bond positional isomers of long chain n-decene were calculated using Hartree-Fock, DFT and correlated ab initio methods. Results were compared to experimental data. Electron correlation was found to be critical for the description of cis-isomer relative energies. Dispersion corrections in the DFT calculations partially compensate for deficiencies and generally improve the agreement with experiment. Adding thermodynamic corrections suffers from the neglect of certain contributions to the entropy of flexible molecules. Accounting for the entropy of mixing of multiple conformers significantly reduces the deviation from experiment. The equilibrium distribution of long chain olefins is reasonably described by correlated QM and also some density functional methods. Computational thermochemistry has thus reached a state where it provides reliable parameters for complex reaction network models and process engineering.

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Application of quantum calculations in the chemical industry—An overview

Cited by 92 publications

References 230 publications

Mathematical modelling of catalytic cracking riser reactor

Mathematical modelling of catalytic cracking riser reactor

How Accurate is the SMD Model for Predicting Free Energy Barriers for Nucleophilic Substitution Reactions in Polar Protic and Dipolar Aprotic Solvents?

The thermochemistry of long chain olefin isomers during hydroformylation

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