The Study of Absorption and Fluorescence Spectra of Nitric Oxide with Synchrotron Radiation
In the absorption spectra, photoabsorption cross sections and oscillator strengths were measured. Quantum defects were calculated to identify the assignments of absorption features. The measured quantities were also compared with previous results. In fluorescence excitation spectra, ultraviolet and visible emissions were observed, and fluorescence cross sections were measured in the excitation region between 140 and 170 nm. The ultraviolet emission is due to the transition B¡¦2£G¡÷X2£S and the visible emission is associated with B¡¦2£G¡÷B2£S and E2£U+¡÷A2£U+ transitions. In the presence of foreign gas, the collisional quenching effect plays an important role on the fluorescence intensity of C(0) and D(0).We measure the quenching half pressure P1/2 of D(0) respectively. The potential well depth of van der Walls molecule NO-M can be derived from the measured quenching half pressure. In contrast to quenching, the fluorescence intensity of C(1), B(9), B(10) and B(11) are enhanced as the pressure of foreign gas is increased. The enchancement of the fluorescence intensity is attributed to the collisional removal of predissociation.
Advisor:Ja-Ba Nee; dong-Po Wang; Chie-Tong Kuo
School:National Sun Yat-Sen University
School Location:China - Taiwan
Source Type:Master's Thesis
Keywords:van der waals well depth collisional quench fluorescence cross section absorption
Date of Publication:07/19/2000