本文利用三維切片式螢光成像法來研究碘化氰分子在第一連續吸收光譜範圍內的光解動態學。實驗於流動槽的環境下進行，蒸氣分壓約維持在五個毫托爾，光解光源為銣釔鋁石榴石雷射系統的四倍頻輸出，而產生的氰基自由基則由雙光子共振光譜技術來偵測。另一方面，在理論架構下所推導出的螢光強度公式可被用來分析由實驗獲取的螢光影像，最後的分析結果可以提供碘化氰分子的躍遷偶極矩以及氰基光解碎片的反彈速度和轉動角動量之間的向量相關性資訊。

The photodissociation dynamics of cyanogen iodide (ICN) in the A continuum was studied by the three-dimensional sliced fluorescence imaging (3DSFI) method. The fourth harmonic of a Nd:YAG laser (266 nm) was used to dissociate a low pressure (5 mTorr) sample of ICN, and the resulting CN photofragments were probed by optical-optical double resonance (OODR) detection scheme. A theoretical framework on the emitted fluorescence intensity has been developed to analyze the experimentally obtained image. The vector correlations among the ICN parent molecule transition dipole moment μ, the CN fragment recoil velocity v and the CN rotational angular moment J can be revealed.

Table of Contents

Chapter 1 Introduction 1

Chapter 2 3DSFI Experiment
2.1 Design concept 4
2.2 Apparatus 6
2.3 Results 8

Chapter 3 Data Analysis
3.1 Energy levels and wave functions of X, A, B states of CN 10
3.2 Density matrices of A ← X and B ← A transitions of CN 15
3.3 Fluorescence intensities of B → X emissions of CN 21
3.4 Vector correlations in the photodissociation of ICN 25

Chapter 4 Conclusions 33

References 34
Figures 36

[1] J. H. Ling and K. R. Wilson, J. Chem. Phys., 1975, 63, 101.
[2] I. Nadler, D. Mahgerefteh, H. Reisler, and C. Wittig, J. Chem. Phys., 1985, 82, 3885.
[3] G. E. Hall, N. Sivakumar, and P. L. Houston, J. Chem. Phys., 1986, 84, 2120.
[4] W. P. Hess and S. R. Leone, J. Chem. Phys., 1987, 86, 3773.
[5] P. L. Houston, J. Chem. Phys., 1987, 91, 5388.
[6] Y. W. Chen and K. M. Chen, J. Chem. Phys., 2010, 133, 126101.
[7] Y. Chen, T. Yang, and K. Chen, Phys. Chem. Chem. Phys., 2009, 11, 7111.
[8] W. Demtrőder, Laser Spectroscopy (Springer-Verlag, Berlin, 1981).
[9] S. P. Davis, and J. P. Phillips, The Red system(A 2Π－X 2S+) of the CN Molecule (University of California Press, Berkeley, 1963).
[10] R. N. Zare, Angular momentum (Wiley, New York, 1988)
[11] K. M. Chen and J. Chang, J. Phys. Chem. A, 1997, 101, 2525.
[12] K. Blum, Density Matrix Theory and Applications (Plenum, New York, 1981)
[13] K. M. Chen and Y. W. Chen, Phys. Chem. Chem. Phys., 2011, 13, 5610.
[14]王夆竹, Master Thesis, National Sun Yat-sen University, 2011.
[15] K. M. Chen and C. C. Pei, J. Chem. Phys., 1999, 15, 7256.