Author: Max BerkowitzPublisher:
ISBN:
Category :
Languages : en
Pages : 150
Book Description
Vibrational Relaxation and Energy Transfer in Solids
Author: Max BerkowitzEffects of Slow Vibrational Relaxation on Anomalous Stokes'-Shifted Luminescence and Energy Transfer in Solids
Author: D. L. DexterPublisher:
ISBN:
Category :
Languages : en
Pages : 19
Book Description
An analysis is presented of the emission spectrum to be expected from model centers in vibrationally excited and electronically excited states. It is shown that for centers which normally exhibit a sizable Stokes' shift there will be, for a short time following excitation, a large component of emission at approximately twice the usual Stokes' shift. This anomalous emission would be detectable by ultra-fast (pico-second) excitation and detection, and in selected systems by conventional means. Its measurement would provide an estimate of the vibrational relaxation time of the center. The implications of the relaxation rate on electronic energy transfer between like species are briefly discussed. (Author).
Energy Transfer and Picosecond Relaxation Processes in Condensed Systems
Author: D. L. DexterPublisher:
ISBN:
Category : Energy transfer
Languages : en
Pages : 13
Book Description
This report contains a brief summary of research performed on optical and mechanical properties of solids, including energy transfer and photo-ionization. The topics discussed include core (X-ray) excitons, effects of magnetic fields on excitons in many-valley semiconductors, simultaneous and cooperative absorption of a photon and energy transfer, effects to be expected because of non-infinite vibrational relaxation rates, a new method for generating sum-rules, and some remarkable products thereof, the angular distribution of electrons in the photo-ionization of polyatomic molecules, and librons in solid N2.
Vibrational Relaxation and Energy Transfer of Matrix Isolated HCl and DCl
Author: Jay Martin WiesenfeldPublisher:
ISBN:
Category :
Languages : en
Pages : 782
Book Description
Le cercle des nations
Author: Vibrational Relaxation and Energy Transfer of Matrix Isolated HCl and DCl
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Vibrational kinetic and spectroscopic studies have been performed on matrix-isolated HCl and DCl between 9 and 20 K. Vibrational relaxation rates for v = 2 and v = 1 were measured by a tunable infrared laser-induced, time-resolved fluorescence technique. In an Ar matrix, vibrational decay times are faster than radiative and it is found that HCl relaxes about 35 times more rapidly than CCl, in spite of the fact that HCl must transfer more energy to the lattice than DCl. This result is explained by postulating that the rate-determining step for vibrational relaxation produces a highly rotationally excited guest in a V yield R step; rotational relaxation into lattice phonons follows rapidly. HCl v = 1, but not v = 2, excitation rapidly diffuses through the sample by a resonant dipole-dipole vibrational energy transfer process. Molecular complexes, and in particular the HCl dimer, relax too rapidly for direct observation, less than or approximately 1 .mu.s, and act as energy sinks in the energy diffusion process. The temperature dependence for all these processes is weak--less than a factor of two between 9 and 20 K. Vibrational relaxation of HCl in N2 and O2 matrices is unobservable, presumably due to rapid V yield V transfer to the host. A V yield R binary collision model for relaxation in solids is successful in explaining the HCl(DCl)/Ar results as well as results of other experimenters. The model considers relaxation to be the result of ''collisions'' due to molecular motion in quantized lattice normal modes--gas phase potential parameters can fit the matrix kinetic data.
Vibrational Energy Transfer in Liquids
Author: Hamzeh Moh'd Abdel-HalimPublisher:
ISBN:
Category : Carbon monoxide lasers
Languages : en
Pages : 328
Book Description
Vibrational and Rotational Relaxation in Gases
Author: James Dewe LambertPublisher: Oxford University Press, USA
ISBN:
Category : Language Arts & Disciplines
Languages : en
Pages : 168
Book Description
Radiationless Transitions
Author: Sheng LinPublisher: Elsevier
ISBN: 0323150276
Category : Science
Languages : en
Pages : 440
Book Description
Radiationless Transitions is a critical discussion of research studies on the theory and experiments in radiationless transitions. This book is composed of nine chapters, and begins with discussions on the theory and experiment of photophysical processes of single vibronic levels and/or single rovibronic levels. The subsequent chapters deal with the spectroscopic investigations of intramolecular vibrational relaxation; the dynamics of molecular excitation by light; and the photophysical processes of small molecules in condensed phase. The discussions then shift to the high pressure effects on molecular luminescence and the internal conversion involving localized excitations, presenting one qualitative and one quantitative example, as well as the intersystem crossing with localized excitations. A chapter explores the energy transfer processes that occur after a molecule in solution is excited by light, with an emphasis on solid solutions in which the large amplitude molecular motion is largely quenched. This chapter also looks into the liquid solutions in which the molecules can translate and rotate under the influence of fluctuating forces from the liquid. The concluding chapter focuses on ultrafast processes. Researchers in the fields of physics, chemistry, and biology will benefit from this book.
Molecular Energy Transfer
Author: Raphael D. LevinePublisher: John Wiley & Sons
ISBN:
Category : Science
Languages : en
Pages : 326
Book Description