Dissertation > Excellent graduate degree dissertation topics show

High Resolution Crossed Molecular Beams Study on the F+H2 Reaction

Author: QiuMingHui
Tutor: WangXiuYan;YangXueMing
School: Dalian Institute of Chemical Physics
Course: Physical and chemical
Keywords: crossed molecular beam H Atom Rydberg Tagging Time-of-Flight differential cross section Feshbach resonance interference
CLC: O643.12
Type: PhD thesis
Year: 2007
Downloads: 100
Quote: 0
Read: Download Dissertation

Abstract


In order to investigate the dynamics and the resonance phenomenon of the F(2P) reactions with H2(j=0,1) in the lower collision energy region, we have developed a new experimental apparatus using the crossed molecular beam technique and the high resolution time-of-flight Rydberg tagging method. There are two new features in this apparatus: a rotating source design such that collision energy can be varied for crossed beam studies of chemical reactions and two rotating detectors for collecting signals at two laboratory angles simultaneously.We have carried out crossed molecular beams scattering studies with full quantum state resolution for F(2P) reactions with H2(j=0,1) in the collision energy range of 0.19~1.20 kcal/mol using the highly sensitive H atom Rydberg tagging time-of-flight method. With the help of theoretical calculations, reactive mechanisms were analyzed.Pronounced forward scattered HF products in the v’=2 vibrational state were clearly observed for the F(2P3/2) +H2(j=0)→HF(v’,j’)+H reaction at the collision energy of 0.52 kcal/mol, which was attributed to both the ground and the first excited Feshbach resonances trapped in the peculiar HF(v’=3)--H’vibrationally adiabatic potential, with significant enhancement due to constructive interference between the two resonances, by full quantum dynamical calculations, carried out using an accurate, full potential energy surface constructed for this study, using high level ab initio methods with small empirical corrections.In addition, effect of single quantum H2-rotation on dynamical resonances in F+H2→HF + H reaction was also investigated. No contribution to the HF(v’=2) product from the two resonances ((003) and (103)) was observed for the H2(j=1) reaction at the collision energy of 0.52 kcal/mol and 0.56 kcal/mol, the H2(j=1) reactions proceed predominantly via the continuum tunneling reaction mechanism, which is a direct reaction processes. There are three components to the HF(v’=2) product: the ground resonance, the excited resonance and the continuum tunneling mechanism for the H2(j=0) reaction at the collision energy of 0.56 kcal/mol, and the contribution of the ground resonance is predominantly forward scattered; The excited resonance component shows a forward-backward scattered peaks, and the forward one is slightly stronger than the backward one; while the continuum tunneling mechanism produces a clear backward scattered distribution. The H2(j=0) reaction at the collision energy of 0.19 kcal/mol proceeds mainly via the continuum tunneling reaction mechanism. While the pronounced forward HF(v’=2) product scattering peak at the H2(j=1) reaction is due to the two Feshbach resonances, (003) and (103).

Related Dissertations

  1. Research on Optical Surface Testing with Interferometers,TG84
  2. Numerical Study of the Effect with Straight and Bowed Stator in Different Axial Gaps,TH45
  3. The Research of a Novel High Efficiency PFC Circuit Based on One Cycle Control,TM46
  4. Analysis of Multiple Access Interference in Asynchronous Direct Sequence Spread Spectrum Communication System Using Gold Sequence,TN914.53
  5. Aerial Target Anti-interference Recognition and Tracking System,TN215
  6. Expression Dynamics of Pheromone Binding Proteins and Expression Influences by Mating and Knockdown of Cryl in Spodoptera Exigua,S433.4
  7. Molecular Cloning, Mrna Expression and Rnai of Nadph-Cytochrome P450 Reductase Gene in Helicoverpa Armigera (Hǘbner),S435.622.3
  8. Effects of BMPR-IB Gene Silencing by Small Interfering RNA on Apoptosis of Porcine Pollicular Granulosa Cells and Ecpression of BMP Pathy-Way-Ralted Genes,S828
  9. Inhibition of Myostatin (MSTN) Expresstion in Primary Porcine Fetal Fibroblasts by Lentivector-mediated RNAi,S828
  10. A Preliminary Study on the Regulation of Hepatoma Cell Biological Behavior by MCFP,R735.7
  11. The DNA Cloning and RNA Interference of Some Functional Genes in Laodelphax Striatellus (Fallen),S435.112.3
  12. The Effect of RNA Interference-mediated ERCC1 Gene on the Chemo-treatment Sensitivity of NSCLC in Vitro,R734.2
  13. The Ecological Adaptation and Interference of Four Submerged Plants Influence of Spirogyra Communis and Cladophora Oligoclona,X524
  14. The Study of Inhibtion Effect by shRNA Expression Vector on Herpes Simplex Virus Type 2 UL54,R346
  15. The Influence of RNA Interference Suppression EphB4 Expression for the PANC-1 Cells of Pancreatic Cancer,R735.9
  16. With backlash compensation function of radial tire building drum,TQ336.1
  17. Experimental Studies on Therapy of Lung Cancer by VEGF-C siRNA Mediated by Liposomes,R734.2
  18. A Study of the Methods to Reduce Peak-to-average Power Ratio of MIMO-OFDM System,TN919.3
  19. Research on Busy Tone Based Mac Protocol in Ad Hoc Network,TN929.5
  20. The Effect of Silencing Spl Gene on Expression of CD59 in Prostate Cancer Cell by RNA Interference,R737.25
  21. Research and Implementation of Anti-Interference Location Algorithm Based on RSSI,TN929.5

CLC: > Mathematical sciences and chemical > Chemistry > Physical Chemistry ( theoretical chemistry ),chemical physics > Chemical kinetics,catalysis > Chemical kinetics > The mechanism and kinetics of chemical reactions
© 2012 www.DissertationTopic.Net  Mobile