Unimolecular Reaction of Methyl Isocyanide to Acetonitrile: A High-Level Theoretical Study

Nguyen, Thanh Lam; Thorpe, James H.; Bross, David H.; Ruscic, Branko; Stanton, John F.

doi:10.1021/acs.jpclett.8b01259

Title: Unimolecular Reaction of Methyl Isocyanide to Acetonitrile: A High-Level Theoretical Study

Abstract

A combination of high-level coupled-cluster calculations and two-dimensional master equation approaches based on semiclassical transition state theory is used to reinvestigate the classic prototype unimolecular isomerization of methyl isocyanide (CH₃NC) to acetonitrile (CH₃CN). The activation energy, reaction enthalpy, and fundamental vibrational frequencies calculated from first-principles agree well with experimental results. In addition, the calculated thermal rate constants adequately reproduce those of experiment over a large range of temperature and pressure in the falloff region, where experimental results are available, and are generally consistent with statistical chemical kinetics theory (such as Rice-Ramsperger-Kassel-Marcus (RRKM) and transition state theory (TST)).

Authors:

Nguyen, Thanh Lam ^[1]; Thorpe, James H. ^[1];

^[2];

^[3];

^[1]

Univ. of Florida, Gainesville, FL (United States)
Argonne National Lab. (ANL), Argonne, IL (United States)
Argonne National Lab. (ANL), Argonne, IL (United States); Univ. of Chicago, IL (United States)

Publication Date:: 2018-04-26

Research Org.:: Argonne National Lab. (ANL), Argonne, IL (United States)

Sponsoring Org.:: USDOE Office of Science (SC), Basic Energy Sciences (BES). Chemical Sciences, Geosciences, and Biosciences Division; Air Force Research Laboratory (AFRL) - Air Force Office of Scientific Research (AFOSR)

OSTI Identifier:: 1461519

Grant/Contract Number:: AC02-06CH11357

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Physical Chemistry Letters

Additional Journal Information:: Journal Volume: 9; Journal Issue: 10; Journal ID: ISSN 1948-7185

Publisher:: American Chemical Society

Country of Publication:: United States

Language:: English

Subject:: 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Active Thermochemical Tables

Citation Formats


                    Nguyen, Thanh Lam, Thorpe, James H., Bross, David H., Ruscic, Branko, and Stanton, John F. Unimolecular Reaction of Methyl Isocyanide to Acetonitrile: A High-Level Theoretical Study.  United States: N. p., 2018. 
Web.  https://doi.org/10.1021/acs.jpclett.8b01259.

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                    Nguyen, Thanh Lam, Thorpe, James H., Bross, David H., Ruscic, Branko, & Stanton, John F. Unimolecular Reaction of Methyl Isocyanide to Acetonitrile: A High-Level Theoretical Study.  United States.  https://doi.org/10.1021/acs.jpclett.8b01259

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                    Nguyen, Thanh Lam, Thorpe, James H., Bross, David H., Ruscic, Branko, and Stanton, John F. Thu .  
"Unimolecular Reaction of Methyl Isocyanide to Acetonitrile: A High-Level Theoretical Study".  United States.  https://doi.org/10.1021/acs.jpclett.8b01259.  https://www.osti.gov/servlets/purl/1461519.

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@article{osti_1461519,

  title        = {Unimolecular Reaction of Methyl Isocyanide to Acetonitrile: A High-Level Theoretical Study},

  author       = {Nguyen, Thanh Lam and Thorpe, James H. and Bross, David H. and Ruscic, Branko and Stanton, John F.},

  abstractNote = {A combination of high-level coupled-cluster calculations and two-dimensional master equation approaches based on semiclassical transition state theory is used to reinvestigate the classic prototype unimolecular isomerization of methyl isocyanide (CH3NC) to acetonitrile (CH3CN). The activation energy, reaction enthalpy, and fundamental vibrational frequencies calculated from first-principles agree well with experimental results. In addition, the calculated thermal rate constants adequately reproduce those of experiment over a large range of temperature and pressure in the falloff region, where experimental results are available, and are generally consistent with statistical chemical kinetics theory (such as Rice-Ramsperger-Kassel-Marcus (RRKM) and transition state theory (TST)).},

  doi          = {10.1021/acs.jpclett.8b01259},

  journal      = {Journal of Physical Chemistry Letters},

  number       = 10,

  volume       = 9,

  place        = {United States},

  year         = {2018},

  month        = {4}

}

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https://doi.org/10.1021/acs.jpclett.8b01259

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Cited by: 14 works

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Works referencing / citing this record:

Single photon ionization of methyl isocyanide and the subsequent unimolecular decomposition of its cation: experiment and theory
journal, January 2019

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DOI: 10.1039/c9cp04310a

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The Journal of Chemical Physics, Vol. 150, Issue 8
DOI: 10.1063/1.5081827

High-accuracy extrapolated ab initio thermochemistry. IV. A modified recipe for computational efficiency
journal, June 2019

Thorpe, James H.; Lopez, Chris A.; Nguyen, Thanh Lam
The Journal of Chemical Physics, Vol. 150, Issue 22
DOI: 10.1063/1.5095937

Is CH ₃ NC isomerization an intrinsic non-RRKM unimolecular reaction?
journal, November 2019

Jayee, Bhumika; Malpathak, Shreyas; Ma, Xinyou
The Journal of Chemical Physics, Vol. 151, Issue 18
DOI: 10.1063/1.5126805

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Title: Unimolecular Reaction of Methyl Isocyanide to Acetonitrile: A High-Level Theoretical Study

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