Presentation Title

Computational Analysis: Reaction Mechanisms for NO2 and CO

Faculty Mentor

Dr. Victor Prutyanov

Start Date

18-11-2017 10:00 AM

End Date

18-11-2017 11:00 AM

Location

BSC-Ursa Minor 125

Session

Poster 1

Type of Presentation

Poster

Subject Area

physical_mathematical_sciences

Abstract

Abstract

Most chemical reactions occur through a sequence of single steps that sum to the overall reaction, and all the single steps together make up the reaction mechanism. For any reaction, there may exists several possible mechanisms that operate under different conditions. The determination of a more proper mechanism requires quantum mechanical examinations of the reaction kinetics and its thermal dynamic energy factors. In this work, two mechanisms of the atom transfer reaction NO2 (g)+CO(g)→CO2 (g)+NO(g) were studied by using long-range corrected hybrid density functional method ωB97X-D and 6-31+G(d,p) and aug-cc-PVQZ basis sets.

Mechanism 1:

Step 1: NO2+NO2 ⇄NOONO2

Step 2: NOONO2 ⇄NO+NO3

Step 3: NO3+CO→NO2+CO2

Mechanism 2: NO2+CO→CO2+NO

The pseudo equilibrium approximation was introduced in the treatment of the kinetic schemes, and the results show that both of the mechanisms are feasible under different conditions.

Summary of research results to be presented

The rate constant for Mechanism 2 is significantly greater than the overall rate constant for Mechanism 1. However, at the initial stages of the reaction, the concentration of NO is very small, which leads to the very large value of the constant. Thus, it can be anticipated that the reaction initially will operate via Mechanism 1. Gradually, when nitrogen monoxide accumulates in the system, Mechanism 2 will start to take over at SATP.

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Nov 18th, 10:00 AM Nov 18th, 11:00 AM

Computational Analysis: Reaction Mechanisms for NO2 and CO

BSC-Ursa Minor 125

Abstract

Most chemical reactions occur through a sequence of single steps that sum to the overall reaction, and all the single steps together make up the reaction mechanism. For any reaction, there may exists several possible mechanisms that operate under different conditions. The determination of a more proper mechanism requires quantum mechanical examinations of the reaction kinetics and its thermal dynamic energy factors. In this work, two mechanisms of the atom transfer reaction NO2 (g)+CO(g)→CO2 (g)+NO(g) were studied by using long-range corrected hybrid density functional method ωB97X-D and 6-31+G(d,p) and aug-cc-PVQZ basis sets.

Mechanism 1:

Step 1: NO2+NO2 ⇄NOONO2

Step 2: NOONO2 ⇄NO+NO3

Step 3: NO3+CO→NO2+CO2

Mechanism 2: NO2+CO→CO2+NO

The pseudo equilibrium approximation was introduced in the treatment of the kinetic schemes, and the results show that both of the mechanisms are feasible under different conditions.