Rotational and vibrational analysis of the CaF B2Σ+–X2Σ+ system

1980 ◽  
Vol 58 (5) ◽  
pp. 703-712 ◽  
Author(s):  
Michael Dulick ◽  
Peter F. Bernath ◽  
Robert W. Field
Keyword(s):  
Fluorescence Detection ◽  
Vibration Analysis ◽  
Vibrational Analysis ◽  
Dye Laser ◽  
Selected Lines ◽  
Excitation Spectra

A rotation–vibration analysis of the CaFB2S+–X2Σ+ system is reported. Excitation spectra of CaF are recorded with a cw, 1 MHz bandwidth, dye laser combined with restricted-bandpass (2 Å) fluorescence detection. The accuracy of line measurements is 0.003 cm−1. Nine bands in the Δν = 0 sequence are analyzed (ν″ = 0–2,8,9, 12–15) and selected lines in four Δν = −1 bands (ν″ = 1–4) are used to obtain band origins needed for the vibrational analysis. The main constants (1σ error in parentheses) for the CaF B2Σ+ state are: Te = 18 841.309(3) cm−1. Be = 0.342604(7) cm−1, ωe = 572.405(36) cm−1, αe = 0.002630(6) cm−1, ωexe = 3.143(13) cm−1, Re = 1.955 Å. The B2Σ+ state is found to be in pure precession with A2Π with l = 1.

Direct comparison of two-photon and one-photon excited fluorescence detection in liquid chromatography using an excimer-pumped dye laser

1991 ◽  
Vol 63 (23) ◽  
pp. 2685-2688 ◽  
Author(s):  
Ronald J. Van de Nesse ◽  
Arjan J. G. Mank ◽  
Gerard P. Hoornweg ◽  
Cees. Gooijer ◽  
Udo A. T. Brinkman ◽  
...  
Keyword(s):  
Liquid Chromatography ◽  
Fluorescence Detection ◽  
Dye Laser ◽  
Two Photon

Theoretical Study on Fluorescence Spectra of Three Coumarin Derivatives

2013 ◽  
Vol 389 ◽  
pp. 25-28 ◽  
Author(s):  
Ying Wang
Keyword(s):  
Fluorescence Spectra ◽  
Vibrational Analysis ◽  
Emission Spectra ◽  
Dft Method ◽  
Excited Configuration ◽  
Coumarin Derivatives ◽  
Excitation Spectra ◽  
Geometric Configurations ◽  
Td Dft ◽  
Experimental Values

The fluorescence spectra of three coumarin derivatives are studied. Geometric configurations of the three compounds are optimized by DFT method of quantum chemistry on B3LYP/6-31G. There is no imaginary frequency in vibrational analysis. Their excitation spectra are calculated by TD-DFT method. Furthermore, geometric configurations in excited state of the three compounds are optimized by CIS method. Based on the excited configuration emission spectra are also calculated. All the calculated results are in good agreement with experimental values.

scholarly journals Photodissociation of Ozone at 248 nm and Vacuum Ultraviolet Laser-Induced Fluorescence Detection of O(1D)

1998 ◽  
Vol 17 (4) ◽  
pp. 191-203 ◽  
Author(s):  
A. M. Sarwaruddin Chowdhury
Keyword(s):  
Fluorescence Detection ◽  
Vacuum Ultraviolet ◽  
Laser Induced Fluorescence ◽  
Dye Laser ◽  
Probe Laser ◽  
Gas Cell ◽  
Ultraviolet Laser ◽  
Laser Induced Fluorescence Detection ◽  
Krf Laser ◽  
Vacuum Ultraviolet Laser

Ozone molecules, O3, were photodissociated in the presence of N2 at 248 nm (KrF laser) to O(1D)+ O2(1∆). The O(1D) atoms were detected by generating vacuum ultraviolet laser-induced fluorescence (VUV LIF) for the 3s1D0 -2p 1D transition at 115.2 nm. The 115.2 nm probe laser was generated by frequency tripling (ω vuv=3ω) of the 345.6 nm PTP dye laser in a Xe gas cell.

Vibration Analysis for Preventive Maintenance: A Classical Case History

1987 ◽  
Vol 24 (04) ◽  
pp. 332-339
Author(s):  
Stephen L. Hofmann
Keyword(s):  
Preventive Maintenance ◽  
Vibration Analysis ◽  
Monitoring Program ◽  
Vibrational Analysis ◽  
Classical Case ◽  
Vibration Monitoring ◽  
Vibration Level ◽  
Engine Vibration ◽  
Main Engine ◽  
Marine Engineers

This paper describes the California Maritime Academy's Vibration Monitoring Program for Preventive Maintenance (PM) onboard the Training Ship Golden Bear(TSGB) and how the program detected a potentially dangerous main engine problem. The discovery of machinery operating faults by using vibrational analysis is not unique to marine engineers, but several factors in the Golden Bear's main engine vibration problem make this case a classical one:the nature and extent of the vibration levels;the timing of events and the way the fault developed;the final location of the fault in relationship to the spot on the engine where the high vibration level occurred; andverification of the fact that a PM vibration program can successfully diagnose faults in operating machinery in the marine environment.

Studies of the Spectral Dependence of Photoionization Spectrometry Measurements of NO in Air

2000 ◽  
Vol 54 (2) ◽  
pp. 190-196 ◽  
Author(s):  
S. A. Elwood ◽  
J. B. Simeonsson
Keyword(s):  
Spectral Dependence ◽  
Laser Excitation ◽  
Limit Of Detection ◽  
Significant Enhancement ◽  
Resonance Ionization ◽  
Signal To Noise ◽  
Selected Lines ◽  
Excitation Spectra ◽  
Near Resonance ◽  
Comparison Measurements

The relative merits of five laser excitation schemes have been evaluated for photoionization spectrometry (PIS) measurements of NO in air. All five schemes utilize wavelengths near 215 nm, which correspond to excitation of rovibronic transitions in the A 2Σ+–X 2πi (1,0) bands of NO. Photoionization of the excited NO molecules is accomplished by using wavelengths ranging from 215 to 1064 nm. Excitation spectra of the five PIS schemes reveal a significant enhancement when 355 nm radiation is used for photoionization. The enhancement is hypothesized to be related to a resonance or near-resonance ionization process for selected lines in the A 2Σ+–X 2π1/2 band [specifically the R11 + Q21 ( J″ = 8.5–12.5) lines and the P21 + Q11 ( J” 9.5–10.5) lines] and the A 2Σ+–X 2π3/2 band [specifically the R12 + Q22 ( J” 8.5–12.5) lines and the P22 + Q12 ( J” = 9.5–10.5) lines] of NO. Comparison measurements using all five schemes demonstrate that the highest sensitivity and highest signal-to-noise ratios are observed by using the 215 nm + 355 nm scheme, for which a limit of detection of 80 parts per trillion by volume for NO in air has been achieved.

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