Journal ArticleDOI
Laser‐Induced 16‐μ Fluorescence in SF6: Acoustic Effects
TLDR
In this article, a laser-induced sound wave propagating in the sample cell is analyzed by solving the coupled mass, momentum, and energy transport equation for the gas following laser excitation.Abstract:
Damped oscillations in the laser‐excited 16‐ and 10‐μ infrared fluorescence decay from SF6 and SF6–rare‐gas mixtures have been observed. This fluorescence modulation is shown to be due to a laser‐induced sound wave propagating in the sample cell. The generation and propagation of this sound wave is analyzed by solving the coupled mass, momentum, and energy transport equation for the gas following laser excitation. Similar effects have been observed in BCl3, and the phenomenon is expected to occur in general for molecular systems which strongly absorb pulsed laser radiation and also have very rapid vibration–vibration and vibration–translation energy transfer rates. The risetime of the 16‐μ fluorescence from SF6 following excitation by a Q‐switch CO2 laser oscillating at 10.6 μ gives a lower limit of 5 × 104 sec−1 at 1 torr for the vibration–vibration energy transfer rate in SF6 between states fluorescing at 10 μ and states fluorescing at 16 μ.read more
Citations
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Journal ArticleDOI
Laser Excitation and Equilibration of Excited Vibrational States in CH3F
TL;DR: In this paper, a CO2 Q-switch laser with the P(20) line of the 9.6-μ band exhibits fluorescence from the ν1 and ν4 modes at 3000 cm−1.
Journal ArticleDOI
Semiclassical theory of collision‐induced vibration–rotational transitions. Application to methylhalides
Adolf Miklavc,Sighart F. Fischer +1 more
TL;DR: In this article, a collision-induced vibrational transition theory of polyatomic molecules is presented, in which the effects of molecular rotation are included, and the molecule itself is considered as a classical top with internal degrees of freedom, treated quantum mechanically.
Journal ArticleDOI
Time‐resolved thermal lensing studies of laser‐induced translational energy fluctuations in CD4, SO2, and OCS
TL;DR: In this article, a generalized spectrophone effect has been observed in mixtures of laser-excited CH3F with CH3Cl, indicating the contribution of endothermic collisional processes to the vibrational relaxation of these molecules.
Journal ArticleDOI
Model for V→ T, R relaxation: CH4 and CD4 mixtures
Paul F. Zittel,C. Bradley Moore +1 more
TL;DR: In this paper, a laser-fluorescence technique is used to determine vibration-to-vibration energy transfer rates for relaxation of HCl and DCl by CH4 and CD4.
Journal ArticleDOI
Laser induced time-dependent thermal lensing studies of vibrational relaxation: translational cooling in CH3F
TL;DR: Time-resolved measurements of the thermal lens effect have been made for CH 3 F, CH 3 CI and C 2 H 4, and an approximate lower limit of 200 msec -1 has been established for the rate of this cooling process, which corresponds to equilibration of the ν 3 and ν 6 states, in a mixture of 0.2 and 10 torr Ar.
References
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Book
Conduction of Heat in Solids
H. S. Carslaw,John Conrad Jaeger +1 more
TL;DR: In this paper, a classic account describes the known exact solutions of problems of heat flow, with detailed discussion of all the most important boundary value problems, including boundary value maximization.
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TL;DR: Molecular theory of gases and liquids as mentioned in this paper, molecular theory of gas and liquids, Molecular theory of liquid and gas, molecular theories of gases, and liquid theory of liquids, مرکز
Journal ArticleDOI
Vibrational Energy Transfer in CO2 Lasers
TL;DR: In this paper, the rate of near-resonant exchange of vibrational energy between CO2 and N2 (ΔE=18 cm−1) has been measured.
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Elementary differential equations
TL;DR: First Order Differential Equations Second Order Linear Equations Higher order linear Equations Series Solution of Second Order linear equations The Laplace Transform Systems of First Order Linear Eqs Numerical Methods Nonlinear Differential Eqs and Stability Answers to Problems Index as discussed by the authors