Author: Kwok-Wing ChowPublisher:
ISBN:
Category :
Languages : en
Pages : 292
Book Description
I. Vacuum-ultraviolet Emission and Absorption Study of Rare-gas Molecules
Author: Kwok-Wing ChowNew Vacuum Ultraviolet Emission Continua in the Rare Gases
Author: Robert E. HuffmanPublisher:
ISBN:
Category : Emission spectroscopy
Languages : en
Pages : 38
Book Description
Several new vacuum ultraviolet-emission continua recently observed in the spectra of the rare gases helium, argon, and xenon are discussed. These spectra were produced with a windowless light source operated as a repetitive condensed discharge and equipped with a differential pumping system to separate the high pressure (up to 800 mm Hg of helium) light source from the 2-m vacuum spectrograph (pressure 1/1000 mm Hg). In helium two continua were observed at pressures above 150 mm in addition to the weaker 600 to 950 angstroms continuum. The brightest extends from about 1050 to above 4000 angstroms and seems connected with greatly enhanced lines of He(II). The other continuum is the completely broadened principal series extending from 584 to about 510 angstroms and containing broadened principal series absorption lines. With argon in a flow system or xenon isolated with a LiF window, previously observed continua were extended from their resonance lines to beyond 3000 angstroms. Details of the experimental observations and possible explanations of these continua are presented. (Author).
High Resolution Vacuum Ultraviolet Spectroscopy of Small Molecules
Author: W. H. ParklinsonPublisher:
ISBN:
Category :
Languages : en
Pages : 8
Book Description
A 6.65 metre vacuum spectrograph operated at a wavelength resolution of 0.0006 nm has been used to study the spectroscopy of rare gas molecules relevant to the development of intense vacuum ultraviolet radiation sources and lasers, and photoabsorption and predissociation processes in molecular nitrogen, which in the 80-100 nm region are important sources of upper atmospheric atomic nitrogen. Absorption spectra of XeHe, XeNe, XeAr, XeKr, KrHe, KrNe, and KrAr have been photographed and interpreted as arising from transitions from bound ground states to bound or free excited electronic states of these van der Waals molecules; bound excited states have been found for XeKr and XeAr. The emission spectrum of diatomic argon in the 100-150 nm region has been found to consist of four band systems all terminating on the ground electronic state; the only discrete band system, that emitted from the lowest excited state, has been analyzed rotationally and characterized spectroscopically as a triplet state for which the long range potential has been estimated. The absorption spectrum of atomic krypton in the 84-124 nm region has been obtained, and excited Rydberg states with principal quantum number as high as 60 have been assigned; the lowest two ionization energies have been accurately determined. High resolution absorption spectra of dipole allowed transition in molecular nitrogen, from the ground state to excited Rydberg and valence states have been rotationally analyzed. Some large anomalies in frequency spacings and relative intensities have been interpreted in terms of strong homogeneous perturbations rather than predissociations. (Author).
Vacuum Ultraviolet Light Sources
Author: Robert E. HuffmanPublisher:
ISBN:
Category : Far ultraviolet radiation
Languages : en
Pages : 28
Book Description
Photophysics and Photochemistry in the Vacuum Ultraviolet
Author: S.P. McGlynnPublisher: Springer Science & Business Media
ISBN: 9400952694
Category : Science
Languages : en
Pages : 953
Book Description
This volume contains the texts of the Invited Lectures pre sented at the NATO Advanced Study Institute PHOTOPHYSICS AND PHOTOCHEMISTRY IN THE VACUUM ULTRAVIOLET, which was held at the Interlaken Lodge in Lake Geneva, Wisconsin USA, August 15-28, 1982. This ASI was the third in a series of NATO Institutes de voted to a study of the physical and chemical transformations undergone by atoms and molecules after absorption of high-energy (VUV
Research in Vacuum Ultraviolet Absorption Processes and Experimental Techniques
Author: John L. RoebberPublisher:
ISBN:
Category :
Languages : en
Pages : 157
Book Description
The results of investigations of absorption and emission processes in gases important in upper atmosphere chemistry and physics by a wide variety of spectroscopic techniques are presented. The principle area studied is the vacuum ultraviolet at wavelength less than 3000 A using monochromators and spectrographs equipped with rare gas continua and hydrogen continua light sources. Sample cells suitable for work at 20K or between room temperature and 650K, gas chromatography apparatus for purifying samples, fluorescence apparatus to obtain the visible and ultraviolet emission spectra of gases excited by vacuum ultraviolet irradiation, an apparatus for flash photolysis studies, and data processing equipment are described. Experimental studies of the absorption spectrum of carbon suboxide, the fluorescence spectrum of the methoxyl radical, the flash photolysis of methyl nitrite and absorption and emission spectra of the products of a microwave discharge through sulfur dioxide are reported. Finally, theoretical calculations on the electronic structure of carbon dioxide and carbon suboxide are discussed. (Author).
Autoionization Spectra of Gases Observed in the Vacuum Ultraviolet
Author: Robert E. HuffmanPublisher:
ISBN:
Category : Gases
Languages : en
Pages : 50
Book Description
VACUUM ULTRAVIOLET STUDIES OF RARE GASES AND RARE GAS MIXTURES EXCITED WITH PULSED HIGH ENERGY ELECTRON BEAMS.
Author: Vacuum Ultraviolet Studies of Molecular Dynamics
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 7
Book Description
Tunable vacuum ultraviolet radiation generated by four-wave mixing will be used to probe collisional energy transfer and photodissociation. Collisional relaxation of the S((1)D) velocity distribution by rare gases has been measured to learn to what extent this simple process can be described by a hard-sphere, elastic interaction. E yielding V transfer was studied from S((1)D) to CO and N2, both by examining the Doppler profile of the relaxed atoms and by direct measurement of the CO(v, J) distribution. Finally, the photodissociation of O3 and N2O have been investigated by monitoring the Doppler profiles of the resulting O((1)D) lines. This integrated program of molecular dynamics studies using vacuum ultraviolet radiation has enhanced our knowledge both of the chemical physics of these basic processes and of the interaction of high energy photons with small molecules found in the upper atmosphere. Vacuum Ultraviolet Light, Molecular Dynamics, Ozone, Nitrous Oxide, CO.
Author: