Multicomponent QM study on the reaction of HOSO + NO 2 with H 2 O: Nuclear quantum effect on structure and reaction energy profile

2018 ◽  
Vol 119 (10) ◽  
pp. e25895 ◽  
Author(s):  
Hideya Sugimoto ◽  
Masanori Tachikawa ◽  
Taro Udagawa
Keyword(s):  
Quantum Effect ◽  
Energy Profile ◽  
Reaction Energy

Primary and Secondary Isotope Effects in the Photooxidation of 2,5-Dimethyl-2,4-hexadiene. Elucidation of the Reaction Energy Profile

1998 ◽  
Vol 63 (18) ◽  
pp. 6390-6393 ◽  
Author(s):  
Georgios Vassilikogiannakis ◽  
Manolis Stratakis ◽  
Michael Orfanopoulos
Keyword(s):  
Isotope Effects ◽  
Energy Profile ◽  
Reaction Energy

A reaction energy profile and fragment attributed molecular system energy change (FAMSEC)-based protocol designed to uncover reaction mechanisms: a case study of the proline-catalysed aldol reaction

2019 ◽  
Vol 21 (30) ◽  
pp. 16694-16705 ◽  
Author(s):  
Ignacy Cukrowski ◽  
George Dhimba ◽  
Darren L. Riley
Keyword(s):  
Reaction Mechanism ◽  
Reaction Mechanisms ◽  
Molecular System ◽  
Chemical Change ◽  
Aldol Reaction ◽  
Energy Profile ◽  
Molecular Fragments ◽  
Reaction Energy ◽  
System Energy

Molecular fragments and their atoms involved in the strongest inter-molecular diatomic and atom–fragment interactions drive a chemical change (explain the reaction mechanism).

scholarly journals Mekanisme Teoritis Pembentukan Senyawa Siklik Hidrokarbon dari Reaksi C4H5 dan C4H2

2020 ◽  
Vol 7 (2) ◽  
pp. 101-106
Author(s):  
Antonius Indarto ◽  
Lienda Handojo
Keyword(s):  
Molecular Structure ◽  
High Temperature ◽  
Aromatic Hydrocarbons ◽  
Reaction Mechanisms ◽  
Room Temperature ◽  
Energy Requirements ◽  
Computational Studies ◽  
Energy Profile ◽  
Reaction Energy ◽  
Polycyclic Aromatic

Acetylene and polyyne are intermediates in the formation of Polycyclic Aromatic Hydrocarbons (PAHs) and soot in combustion or pyrolysis. PAH formation from acetylene is known as the most adopted pathway because it has a low reaction energy. Another mechanism for the formation of PAH is a mechanism that involves polyyne or known as a radical pathway, proposed by Krestinin. This pathway involves the reaction of alkyne + alkenes which results in the addition of radical sites to the molecular structure. In this study, the two reaction mechanisms will be compared. Electronic features and energy requirements of the reaction process will be evaluated using molecular computational studies based on electron density (DFT). In combustion conditions (high temperature), the formation of radical sites requires relatively little energy, with a range of 2-5 kcal/mol. This is very different when compared to the energy profile for the same reaction at room temperature. From this study, it can be concluded that the mechanism of radical growth has the potential to occur in combustion reactions.Polycyclic aromatic hydrocarbons, radical growth, combustion, polyyne.

In situ study of electron beam-induced chemical vapor deposition of Au in an environmental TEM

1995 ◽  
Vol 53 ◽  
pp. 256-257
Author(s):  
J. Drucker ◽  
R. Sharma ◽  
J. Kouvetakis ◽  
K.H.J. Weiss
Keyword(s):  
Electron Beam ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Quantum Effect ◽  
Line Drawing ◽  
Chemical Vapor ◽  
Environmental Cell ◽  
Engineering Changes ◽  
Kinetics Of

Patterning of metals is a key element in the fabrication of integrated microelectronics. For circuit repair and engineering changes constructive lithography, writing techniques, based on electron, ion or photon beam-induced decomposition of precursor molecule and its deposition on top of a structure have gained wide acceptance Recently, scanning probe techniques have been used for line drawing and wire growth of W on a silicon substrate for quantum effect devices. The kinetics of electron beam induced W deposition from WF6 gas has been studied by adsorbing the gas on SiO2 surface and measuring the growth in a TEM for various exposure times. Our environmental cell allows us to control not only electron exposure time but also the gas pressure flow and the temperature. We have studied the growth kinetics of Au Chemical vapor deposition (CVD), in situ, at different temperatures with/without the electron beam on highly clean Si surfaces in an environmental cell fitted inside a TEM column.

THE LIOUVILLE THEOREM INVOLVING QUANTUM EFFECT

1986 ◽  
Vol 6 (2) ◽  
pp. 201-211 ◽  
Author(s):  
Keda Bao ◽  
Fusui Liu
Keyword(s):  
Liouville Theorem ◽  
Quantum Effect

Mechanisms of ATP to cAMP Conversion Catalyzed by the Mammalian Adenylyl Cyclase: A Role of Magnesium Coordination Shells and Proton Wires

2019 ◽  
Author(s):  
Bella Grigorenko ◽  
Igor Polyakov ◽  
Alexander Nemukhin
Keyword(s):  
Adenylyl Cyclase ◽  
Bond Cleavage ◽  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
Md Simulations ◽  
Coordination Shell ◽  
Energy Profile ◽  
One Step ◽  
Type V

<p>We report a mechanism of adenosine triphosphate (ATP) to cyclic adenosine monophosphate (cAMP) conversion by the mammalian type V adenylyl cyclase revealed in molecular dynamics (MD) and quantum mechanics/molecular mechanics (QM/MM) simulations. We characterize a set of computationally derived enzyme-substrate (ES) structures showing an important role of coordination shells of magnesium ions in the solvent accessible active site. Several stable six-fold coordination shells of Mg<sub>A</sub><sup>2+ </sup>are observed in MD simulations of ES complexes. In the lowest energy ES conformation, the coordination shell of Mg<sub>A</sub><sup>2+ </sup>does not include the O<sub>δ1</sub> atom of the conserved Asp440 residue. Starting from this conformation, a one-step reaction mechanism is characterized which includes proton transfer from the ribose O<sup>3'</sup>H<sup>3' </sup>group in ATP to Asp440 via a shuttling water molecule and P<sup>A</sup>-O<sup>3A</sup> bond cleavage and O<sup>3'</sup>-P<sup>A</sup> bond formation. The energy profile of this route is consistent with the observed reaction kinetics. In a higher energy ES conformation, Mg<sub>A</sub><sup>2+</sup> is bound to the O<sub>δ1</sub>(Asp440) atom as suggested in the relevant crystal structure of the protein with a substrate analog. The computed energy profile initiated by this ES is characterized by higher energy expenses to complete the reaction. Consistently with experimental data, we show that the Asp440Ala mutant of the enzyme should exhibit a reduced but retained activity. All considered reaction pathways include proton wires from the O<sup>3'</sup>H<sup>3' </sup>group via shuttling water molecules. </p>

Survey for Transition of Normal Reaction

2018 ◽  
Vol 5 (3) ◽  
Author(s):  
Hassan Akbari Rahimi
Keyword(s):  
Transition State ◽  
Reactive Intermediates ◽  
The State ◽  
Energy Profile ◽  
Normal Reaction ◽  
Unstable Molecules ◽  
The Difference ◽  
Bond Vibration ◽  
Unstable Molecule ◽  
Profile Diagram

Transition of reaction is a short-lived unstable molecule in a reaction which is formed in between the reaction when reactants change into products. Whereas, transition state is just the state before formation of new molecule (involves breaking of bonds of reactants and formation of new ones) Transition of reaction differs from a transition state in that the intermediate has a discrete lifetime (be it a few nanoseconds or many days), whereas a transition state lasts for just one bond vibration cycle. Intermediates may be unstable molecules (in which case they are called reactive intermediates) or highly stable molecules. The difference between them can be better described through the energy profile diagram.

Energy Profile Summary for North River WWTP Cogeneration Upgrades

2015 ◽  
Vol 2015 (2) ◽  
pp. 1-28
Author(s):  
Tia Trate ◽  
Stephen Tarallo ◽  
Anthony Fiore ◽  
James Lauria
Keyword(s):  
Energy Profile
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