Author: Julie Alexandra MuellerPublisher:
ISBN:
Category :
Languages : en
Pages : 456
Book Description
Photodissociation and Energy Transfer
Author: Julie Alexandra MuellerPublisher:
ISBN:
Category :
Languages : en
Pages : 456
Book Description
Energy Transfer and Vibrationally Mediated Photodissociation in Liquids
Author: F. CrimPublisher:
ISBN:
Category :
Languages : en
Pages : 11
Book Description
Vibrational energy is a central aspect of chemical reactivity. Because a few vibrationally energized molecules are the ones that actually overcome the barriers to reaction to form products, the means by which molecules acquire and lose energy is at the heart of chemistry. Thus, vibrationally excited molecules are important in an enormous variety of environments, ranging from the conventional, such as solutions, to the exotic, such as plasmas. The authors have extended their previous studies of the energy transfer and photodissociation dynamics of isolated molecules into the more complex environment of liquids with the goal of understanding the role that solvents play in the behavior of vibrationally excited molecules. In these experiments, a 100-fs pulse of near or mid-infrared light excites a high frequency stretching vibration of a solute molecule and another short pulse of ultraviolet light monitors the energy content of a subset of the vibrations by transient absorption. The measurements have revealed the influence that vibrational state structure and solvent interactions have on the flow of energy within the vibrationally excited molecule and into the surrounding solvent. (4 figures, 28 refs.)
Time Resolved Energy Transfer and Photodissociation of Vibrationally Excited Molecules
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 10
Book Description
These experiments use ultrafast laser spectroscopy to study reaction and photodissociation dynamics in solution, probing both photodissociation and intramolecular energy transfer. They have observed the photodissociation dynamics of methylhypochlorite (CH3OCl) in different solvents by monitoring the disappearance of the Cl atom and have compared the flow of energy in vibrationally excited methyl iodide (CH3l) in solution and in the gas phase. This second experiment is one of the few direct comparisons of intramolecular vibrational energy flow in a solvated molecule with that in the same molecule isolated in a gas. Because of the importance of vibrational relaxation of molecules after photoisomerization, the other goal has been to probe the vibrational energy flow in both cis and trans-stilbene, a prototypical molecule for cis-trans isomerization.
Studies of Vibrational Energy Transfer and Photodissociation Dynamics
Author: Mark David MoserPhotodissociation Dynamics and Collision Energy Transfer of Highly Excited SO2
Author: Jianqiang MaPublisher:
ISBN:
Category :
Languages : en
Pages : 130
Book Description
As one of the simplest tri-atomic molecules, SO2 is extremely important in various fields in chemistry. SO2 is released by volcanoes and various industrial processes including combustion of sulfur containing fuel, and is well known to be the key chemical that causes the acid rain on earth. Therefore, SO2 has been studied intensively in both atmospheric chemistry as well as combustion chemistry. SO2 has also been discovered in extraterrestrial environment. For example, it is reported to be the most abundant gas observed in the atmosphere of Jupiter's moon, Io[1]. It has therefore generated great interests in the planetary chemistry as well. Even though understanding the structure, spectroscopy and reaction dynamics of SO2 has been of great and fundamental interests for more than 50 years, there are yet some very interesting topics, particularly those related to highly excited SO2, that require further investigations. In this thesis, we combine time-resolved Fourier transform infrared emission spectroscopy with theoretical modeling to study selected interesting problems relevant to highly excited SO2. First, the photodissociation of SO2 molecule by 193 nm photons is investigated. The role of different predissociation channels of electronically excited SO2 is carefully defined. Secondly, the excitation of SO2 by hot H atoms, a topic important in combustion and atmospheric chemistry, is examined. The energy transfer mechanism is identified and discussed. This newly discovered energy transfer mechanism involves the formation of the reactive intermediate species, which will greatly enhance the energy transfer efficiency on top of the classical impulsive type of collision mechanisms. In addition, the collision quenching of highly vibrationally excited SO2 with about 32,000 cm-1 energy is studied. It is found that the long range interactions contribute significantly to vibration to vibration (V-V) energy transfer. The contributions from both long range and impulsive mechanisms are discussed in detail. The studies presented in this thesis have provided important insight on the collision energy transfer and reaction dynamics of highly excited SO2 that would be useful in assessing the behavior of this important molecule in atmospheric, planetary, and combustive environments.
Advances in Photochemistry
Author: David H. VolmanPublisher: John Wiley & Sons
ISBN: 047013366X
Category : Science
Languages : en
Pages : 488
Book Description
Setting the pace for progress and innovation . . . "[Provides] a wealth of information on frontier photochemistry . . . could easily serve as a definitive source of background information for future researchers." —Journal of the American Chemical Society "The overall quality of the series and the timeliness of selections and authors warrants continuation of the series by any library wishing to maintain a first-rate reference series to the literature." —Physics Today ADVANCES IN PHOTOCHEMISTRY More than a simple survey of the current literature, Advances in Photochemistry offers critical evaluations written by internationally recognized experts. These pioneering scientists offer unique and varied points of view of the existing data. Their articles are challenging as well as provocative and are intended to stimulate discussion, promote further research, and encourage new developments in the field.
Gas Kinetics and Energy Transfer
Author: P G AshmorePublisher: Royal Society of Chemistry
ISBN: 1847556108
Category : Science
Languages : en
Pages : 406
Book Description
Specialist Periodical Reports provide systematic and detailed review coverage of progress in the major areas of chemical research. Written by experts in their specialist fields the series creates a unique service for the active research chemist, supplying regular critical in-depth accounts of progress in particular areas of chemistry. For over 80 years the Royal Society of Chemistry and its predecessor, the Chemical Society, have been publishing reports charting developments in chemistry, which originally took the form of Annual Reports. However, by 1967 the whole spectrum of chemistry could no longer be contained within one volume and the series Specialist Periodical Reports was born. The Annual Reports themselves still existed but were divided into two, and subsequently three, volumes covering Inorganic, Organic and Physical Chemistry. For more general coverage of the highlights in chemistry they remain a 'must'. Since that time the SPR series has altered according to the fluctuating degree of activity in various fields of chemistry. Some titles have remained unchanged, while others have altered their emphasis along with their titles; some have been combined under a new name whereas others have had to be discontinued. The current list of Specialist Periodical Reports can be seen on the inside flap of this volume.
Photodissociation Dynamics
Author: Reinhard SchinkePublisher: Cambridge University Press
ISBN: 9780521484145
Category : Science
Languages : en
Pages : 446
Book Description
Photodissociation induced by the absorption of single photons permits the detailed study of molecular dynamics such as the breaking of bonds, internal energy transfer and radiationless transitions. The availability of powerful lasers operating over a wide frequency range has stimulated rapid development of new experimental techniques which make it possible to analyse photodissociation processes in unprecedented detail. This text elucidates the achievements in calculating photodissociation cross-sections and fragment state distributions from first principles, starting from multi-dimensional potential energy surfaces and the Schrödinger equation of nuclear motion. Following an extended introduction in which the various types of observables are outlined, the book summarises the basic theoretical tools, namely the time-independent and the time-dependent quantum mechanical approaches as well as the classical picture of photodissociation. The discussions of absorption spectra, diffuse vibrational structures, the vibrational and rotational state distributions of the photofragments form the core of the book. More specific topics such as the dissociation of vibrationally excited molecules, emission during dissociation, or nonadiabatic effects are also discussed. It will be of interest to graduate students and senior scientists working in molecular physics, spectroscopy, molecular collisions and molecular kinetics.
Diode Laser Probes of Photodissociation, Chemical Reactions, and Vibrational Energy Transfer
Author: Yongsik LeeUltrafast Studies of Photodissociation in Solution
Author: Jason Christopher KingPublisher:
ISBN:
Category :
Languages : en
Pages : 258
Book Description