利用雙光子共振螢光減量光譜法 ( Optical–Optical Double Resonance Fluorescence Depletion Spectroscopy；OODR-FDS ) 來研究雙原子鈉分子7-91Pg高能位電子態。實驗中使用兩步驟雙光子共振激發方式，以B1Pu電子態的振轉能級為中間態，其躍遷方程式如下：
B1Pu ( v’, J’ ) ß X1S+g ( v’’, J’’ ) + hn1
71Pg ( v, J ) ß B1Pu ( v’, J’ ) + hn2
第一道雷射將鈉分子從X1S+g 能態先激發至B1Pu能態，第二道雷射則再將鈉分子激發至71Pg能態。而偵測方法則是偵測從B1Pu能態，躍遷至X1S+g 能態螢光減量的訊號。81Pg、91Pg的激發及偵測方式和71Pg相同。
偵測方法：
B1Pu ( v’, J’ ) ® X1S+g ( v ”, J” ) + hn3 ( Fluo. )
實驗偵測能量範圍為38100～39700 cm-1，共觀察到71Pg電子態100個振轉能級，其中包含了11個振動能級( v=13～23 )；81Pg電子態90個振轉能級，包含13個振動能級( v=7～19 ) ；而91Pg電子態則有40個振轉能級，包含8個振動能級( v=8～15 )。利用非線性擬合程式計算得7-91Pg能態分子常數，並建立其位能曲線。

The Na2 7-91Pg high-lying electronic states have been observed by a pulsed optical-optical double resonance fluorescence depletion spectroscopic technique. In our experiments, we applied the stepwise OODR excitation and several rovibrational levels of the B1Pu electronic states have been used as the intermediate. The transitions can be described as the following processes.
B1Pu ( v’, J’ ) ß X1S+g ( v’’, J’’ ) + hn1
71Pg ( v, J ) ß B1Pu ( v’, J’ ) + hn2
The first dye laser beam excites Na2 molecules from the X1S+g state to the B1Pu, and then the second dye laser beam further excites molecules to the higher excited state 71Pg ( v, J ). The OODR spectra of the Na2 71Pg state have been observed by monitoring the fluorescence depletion of the B1Pu to the X1S+g state. The excitation and detection methods of 81Pg and 91Pg are the same with 71Pg state.
The detection method of this experiment:
B1Pu ( v’, J’ ) ® X1S+g ( v ”, J” ) + hn3 ( Fluo. )
In the energy region 38100～39700 cm-1, We have observed 100 rovibrational levels of 71Pg state, 90 rovibrational levels of 81Pg state, and 40 rovibrational levels of 91Pg state. They are assigned to the 71Pg v=13-23 levels, the 81Pg v=13-23 levels, and the v=8-15 vibrational levels of the 91Pg state. A set of Dunham-type coefficients and Rydberg-Klein-Rees (RKR) potential energy curves for the 7-91Pg states are determined from spectroscopic data.

1. G. Herzberg, "Molecular Spectra and Molecular Structure: Vol. 1, Spectra of Diatomic Molecules", Robert E. Krieger Publishing Co., Malabar, Florida (1989).
2. N. W. Carlson, A. J. Taylor, K. M. Jones, and A. L. Schawlow, Phys. Rev. A 24, 822 (1981).
3.A. J. Taylor, K. M. Jones, and A. L. Schawlow, J. Opt. Soc. Am. 73, 994 (1983).
4. A. Alikacem and M. Aubert-Frecon, J. Mol. Spectrosc. 97, 343 (1983).
5. C. Effantin, J. d’Incan, A. J. Ross, R. P. Barrow, and J. Verges, J. Phys. B: At. Mol. Phys. 15, 1515 (1984).
6. T. J. Whang, H. Wang, A. M. Lyyra, Li Li, and W. C. Stwalley, J. Mol. Spectrosc. 145, 112 (1991).
7.C. C. Tsai, Ph.D. dissertation, The University of Iowa, 1993.
8.C. C. Tsai, J. T. Bahns and W. C. Stwalley, J. Mol. Spectrosc.167, 437 (1994).
9.S. Magnier, Millie Ph, Dulieu et al. J. Chem. Phys. , 98, 7113 (1993).
10. Li. Li, and R. W. Field, J. Mol. Spectrosc. 117, 245 (1986).
11.T. J. Whang, W. C. Stwalley, Li. Li, and A. M. Lyyra, J. Mol. Spectrosc. 155, 184 (1992).
12.T. J. Whang, W. C. Stwalley, Li. Li, and A. M. Lyyra, J. Mol. Spectrosc. 157, 544 (1993).
13. Li. Li, Q. Zhu, and R. W. Field, Mol. Phys. 66, 685 (1989).
14. Li. Li and M. Li, J. Mol. Spectrosc. 173, 25 (1995).
15. J. Li, Y. Liu, H. Chen, H. Gao, J. Xiang, D. Chen, G. Wu, Li. Li, and R. W. Field, J. Chem. Phys. 108, 7707 (1998).
16. X. Xie, R. W. Field, Li. Li, A. M. Lyyra, J. T. Bahns, and W. C. Stwalley, J. Mol. Spectrosc. 134,119 (1989).
17. Y. Liu, J. Li, H. Gao, D. Chen, Li. Li, R. W. Field, and A. M. Lyyra, J. Chem. Phys. 108, 2269 (1998).
18. Y. Liu, J. Li, H. Chen, D. Chen, Li. Li, and R. W. Field, J. Mol. Spectrosc. 192,32 (1998).
19. Li. Li, A. M. Lyyra, and W. C. Stwalley, J. Mol. Spectrosc. 134,113 (1989).
20. J. Li, Y. Liu, M. Xue, D. Chen, and Li. Li, Mol. Spectrosc. 175,13 (1996).
21. Y. Liu, J. Li, M. Xue, D. Chen, Li. Li, and G. H. Jeung, J. Chem. Phys. 103, 7213 (1995).
22. Y. Liu, J. Li, D. Chen, Li. Li, K. M. Jones, B. Ji, and R. Le Roy, J. Chem. Phys. 111, 3494 (1999).
23.李麗等人，光譜學與光譜分析。第91卷，第1期，1999年二月。
24. Li Li and R. W. Field, J. Phys. Chem. 87, 3020 (1983).
25. X. Xie and R. W. Field, Chem Phys. 99, 337 (1985).
26.T. J. Whang, C. C. Tsai, A. M. Lyyra, Li Li, and W. C. Stwalley, J. Mol. Spectrosc. 160,411 (1993).
27.A. Yiannopoulou, K. Urbanski, A. M. Lyyra, L. Li, B. Ji, J. T. Bahns, and W. C. Stwalley, J. Chem. Phys. 102 (8), 3024 (1995).
28.W. Demtröder,“Laser Spectroscopy”, Springer-Verlag, Berlin, 569 (1981).
29. R. Rydberg, Z. Physik, 73, 376 (1931).
30. O. Klein, Z. Physik, 76, 226 (1932).
31. R. Rydberg, Z. Physik, 80, 514 (1933).
32. A. L. G. Rees, Proc. Phys. Soc. (London), 59, 998 (1947).
33. J. T. Vanderslice, E. A. Mason, W. G. Maisch, and E. R. Lippincott, J. Mol. Spectrosc. 3, 17 (1959).
34. R. N. Zare, J. Chem. Phys. 40,1934 (1964).
35. J. L. Dunham, Phys. Rev. 41, 721 (1932).
36. B. H. Bransden and C. J. Joachain, "Physics of Atoms and Molecules", Addison Wesley Longman Limited, London. (1983)
37. H. Hönl and F. London, Z. Physik 33, 803 (1925)
38.丁勝懋，“雷射工程導論”，(第三版，中央出版社出版，1993)
39. W. Demtröer, M. McClintock, and R. N. Zare, J. Chem. Phys. 51, 5495 (1969).
40. H. M. Crosswhite, J. Res. of National Bureau of standard-A. Phys. and Chem. 79, No.1, 17-69. (1975).
41. Xinming Zhu, Abdullahi H. Nur, and Prabhakar Misra, J Quant. Spectrosc. Radiat Transfer, 52, 167-177. (1994).
42. Victor Kaufman and Bengt Edlen, J. Phys. Chem. Ref. Data, 3, 506 (1974).
43. S. Gerstenkorn and P. Luc,“Atlas du Spectre D’Absorption de la Molecule d’Iode”, CNRS, Paris, 1978
44. S. Gerstenkorn and P. Luc, Rev. Phys. Appl. 14, 791 (1979).
45. P. Kusch and M. M. Hessel, J Chem. Phys. 68(6), 25991. (1978).
46. W. J. Stevens, M. M. Hessel, P. J. Bertoncin, and A. C. Wahl, J Chem. Phys. 66, 1477 (1977).
47. W. Wood and F. E. Hackeet, Astrophys. J. 30, 339 (1909).
48. W. R. Fredrickson and C. R. Stannard, Phys. Rev. 44, 632 (1933).
49. T. Carroll, Phys. Rev. 52, 822 (1937).
50. P. Kusch and M. M. Hessel, J Chem. Phys. 63(9), 4087 (1975).
51. Li. Li, Y. Liu, J. Xiang, and A. M. Lyyra, Journal of the Chinese Chemical Society, 48, 291 (2001).
52. Y. L. Pan, L. S. Ma, L. E. Ding, Z. G. Wang, and D. P. Sun, J. Mol. Spectrosc. 162, 178 (1993).
53.胡思儀，“雙原子鈉分子71Pg能態”， 國立成功大學化學所碩士論文(1999年七月).