Chi-Kung Kenny Ni

Research Fellow
Adjunct Associate Professor at Department of Chemistry, National Tsing Hua University, Taiwan

Education

1985 B.S. Tsing Hua University, Taiwan
1993 Ph.D. Columbia University, USA
1993~95 Postdoc. University of California, Berkeley, USA

Positions of Postdoc, Research Assistant, and Ph.D. student fellowships are available most of the time. If you are interested in our research, please contact me by e-mail: ckni@po.iams.sinica.edu.tw

Research Interests

My research interests include two areas.

(a)          Photodissociation dynamics of organic molecules and small biomolecules in the molecular beam.

(b)         Energy transfer of highly vibrational excited molecules.

(a) A new technique, multimass ion imaging, was developed in our laboratory to study the photofragment translational spectroscopy. The advantage of this technique is that translational spectroscopy of many different photofragments can be measured simultaneously. Figure 1 shows part of the photofragment ion images obtained from photodissociation of C6H5CD3 at 193 nm.

A new isomerization mechanism of aromatic molecules was observed from these studies. The significance of this isomerization is that the carbon atoms and hydrogen atoms belonging to the alkyl group are involved in an exchange with those atoms in the aromatic ring during isomerization. Photodissociation dynamics of the other aromatic molecules, including benzene, toluene, xylene, ethylbenzene, propylbenzene, fluorobenzene, fluorotoluene, benzotrifluoride, pyridine, methyl-pyridine, phenol, aniline, nitrosobenzene, nitrobenzene, indole, … were investigated.

(b) Collisional energy transfer of highly vibrationally excited molecules is one of the important processes in many chemical reactions. Lindemann's formulation for unimolecular reactions involves three elementary steps, i.e., activation, deactivation and reaction. The derivation of the Lindemann mechanism is based on the explicit assumption that collisions are strong or efficient enough in transporting molecules up and down the energy ladder to maintain the equilibrium Boltzmann distribution of reactants. Studies of unimolecular reactions have revealed that most collisions are far less efficient than strong collisions. However, recent experimental and classical trajectory calculations show that a small fraction of collisions transfer inordinate amounts of energy. Simulated collisional energy-transfer probability distributions exhibit a tail at high energies. These large energy transfer collisional encounters are called supercollisions. Here we examine the energy transfer of highly vibrationally excited molecules using a crossed-beam apparatus in conjunction with vacuum ultraviolet photoionization and time-sliced ion imaging techniques. Figure 2 shows the Newton diagram and time-sliced ion image of scattered highly vibrationally excited azulene from the collisions with Kr atoms in a crossed-molecular beam apparatus. Supercollisions were observed direction from the backward scattering.

Group Photo (2004.8)  

Recent Publications (SCI Papers since 2001) 

1.      Shang-Ting Tsai, Chih-Kai Lin, Yuan T. Lee and Chi-Kung Ni, Multimass Ion Imaging Detection: Application to Photodissociation, Review of Scientific Instruments, 72, 1963, (2001).

2.      Cheng-Liang Huang, Shan-Shan Ju, Anthony J. Merer, Chi-Kung Ni, A. H.Kung, and I-Chia Chen, Spectra of jet-cooled 32SO2 and 34SO2 in systems a3B1-X1A1, rotational structure of perturbed b3A2. J. Chem. Phys. 114, 1187, (2001).

3.      Shang-Ting Tsai, Cheng-Liang Huang, Yuan T. Lee and Chi-Kung Ni, Ring opening dissociation of d6-benzene, J. Chem. Phys. 115, 2449, (2001).

4.      Yung-Ching Chou, Cheng-Liang Huang, I-Chia Chen, Chi-Kung Ni, and A. H. Kung, Rotational resolved spectra of transitions involving motion of the methyl group of acetaldehyde in the system A1A”-X1A, J. Chem. Phys. 115, 5089 (2001).

5.      Cheng-Liang Huang, Jyh-Chiang Jiang, Yuan T. Lee, S. H. Lin, and Chi-Kung Ni, Photodissociation and photoisomerization of small aromatic molecules in molecular beam. Aust. J. Chem. 54, 561, (2001)(invited review article).

6.      Yung-Ching Chou, Cheng-Liang Huang, I-Chia Chen, Chi-Kung Ni, and A. H.Kung, Rotational resolved spectra of transitions involving methyl torsion and C-C-O bend of acetaldehyde in the system of A1A”-X1A, J. Chem. Phys. 116, 1003 (2002).

7.      Chih-Kai Lin, Cheng-Liang Huang, Jyh-Chiang Jiang, H. Chang, S. H. Lin, Yuan T. Lee, and Chi-Kung Ni, Photoisomerization and photodissociation of toluene in molecular beam. J. Am. Chem. Soc.124, 4068 (2002).

8.      W. J. Chen, T. K. Fang, T. N. Chang, T. S. Yih, C. K. Ni, and A. H. Kung, The 3snd 1D to the 3png 1F autoionization resonances of Mg, Phys. Rev. A 65(3)art no:032717 (2002).

9.      Cheng-Liang Huang, Jyh-Chiang Jiang, S. H. Lin, Yuan T. Lee, and Chi-Kung Ni, Photodissociation of ethylbenzene at 248 nm, J. Chem. Phys. 116, 7779 (2002) (communication).

10.  C. H. Chang, Cheng-Liang Huang, Chi-Kung Ni, H. L. Dai, M. Hayashi, K. K. Liang, Andy Kung, I. C. Chen, and S. H. Lin, Experimental and theoretical studies of the effects of collisions and magnetic fields on quantum beat, Molecular Physics, 100, 1117 (2002).

11.  Cheng-Liang Huang, Hon-Huei Liu, Chen-Lin Liu, A. H. Kung, and Chi-Kung Ni, Rotationally resolved laser-induced fluorescence of biacetyl in A1Au–X1Ag, J. Chem. Phys. 117, 5165 (2002).

12.  Cheng-Liang Huang, Jyh-Chiang Jiang, Yuan T. Lee, and Chi-Kung Ni, Photodissociation of ethylbenzene and n-propylbenzene in a molecular beam, J. Chem. Phys. 117, 7034 (2002).

13.  Yung-Ching Chou, Cheng-Liang Huang, I-Chia Chen, Chi-Kung Ni, and A. H. Kung, Rotationally resolved structures in the fifth and sixth torsional states of A1A”acetaldehyde: Internal rotation above the torsional barrier, J. Chem. Phys. 117 7906 (2002).

14.  Cheng-Liang Huang, Jyh-Chiang Jiang, Yuan T. Lee, and Chi-Kung Ni, Photoisomerization and photodissociation of m-xylene in a molecular beam, J. Phys. Chem. A. 107, 4019, (2003).

15.  Ming-Fu Lin, Cheng-Liang Huang, Yuan T. Lee, and Chi-Kung Ni, Photodissociation dynamics of azulene, J. Chem. Phys. 119, 2032, (2003).

16.  Cheng-Liang Huang, Jyh-Chiang Jiang, Alex Mebel, Yuan T. Lee, and Chi-Kung Ni, Photodissociation dynamics of fluorobenzene, J. Am. Chem. Soc. 125, 9814, (2003).

17.  C. H. Chang, C. L.Huang, C. K. Ni, H. L. Dai, M. Hayashi, K. K. Liang, A. Kung, I. C. Chen, S. H. Lin, Experimental and theoretical studies of quantum beats in fluorescence, J. Chin. Chem. Soc.(Taipei) 50, 631 (2003).

18.  Ming-Fu Lin, Cheng-Liang Huang, Yuan T. Lee, and Chi-Kung Ni, H and CH3 eliminations in the photodissociation of chlorotoluene, J. Chem. Phys. 119, 7701 (2003).

19.  Chien-Ming Tseng, Cheng-Liang Huang, Yuan T. Lee, and Chi-Kung Ni, Multimass ion imaging detection: Application to photodissociation. Chemistry, The Chinese Chem Soc., Taipei, 61, 401 (2003).

20.  Shang-Ting Tsai, Jyh-Chiang Jiang, Ming-Fu Lin, Yuan T. Lee, and Chi-Kung Ni, Carbon–carbon bond cleavage in the photoionization of ethanol and 1-propanol clusters, J. Chem. Phys. 120, 8979, (2004).

21.  Cheng-Ming Tzeng,Y. M. Choi, Cheng-Liang Huang, Chi-Kung Ni,Yuan T. Lee, and M. C. Lin, Photodissociation of nitrosobenzene and decomposition of phenyl radical, J. Phys. Chem. A. 108, 7928 (2004).

22.  Chi-Kung Ni and Yuan T. Lee, Photodissociation of simple aromatic molecules in a Molecular Beam, International review in physical chemistry 23, 187 (2004).

23.  Chien-Ming Tseng, Yuri A. Dyakov, Cheng-Liang Huang, Alexander M. Mebel, Sheng Hsien Lin, Yuan T. Lee, and Chi-Kung Ni, Photoisomerization and photodissociation of aniline and 4-methylpyridine, J. Am. Chem. Soc. 126, 8760 (2004).

24.  Chien-Ming Tseng, Yuan T. Lee, and Chi-Kung Ni, H atom elimination from the πσ* state in the photodissociation of phenol, J. Chem. Phys. 121, 2459 (2004)(communication)

25.  Ming-Fu Lin, Yuri A. Dyakov, Sheng Hsien Lin, Yuan T. Lee, and Chi-Kung Ni, Photodissociation dynamics of C6HxF6-x (x=1~4) at 193 nm, J. Phys. Chem. B. 109, 8344 (2005).

26.  Chen-Lin Liu, H. C. Hsu, Chi-Kung Ni, Time-sliced ion imaging study of I2 and I2

1.          + photolysis at 532 nm, Phys. Chem. Chem. Phys. 7, 2151 (2005).

27.  Cheng-Liang Huang, Yuri A. Dyakov, S. H. Lin, Yuan T. Lee, Chi-Kung Ni, Photodissociation dynamics of ethyltoluene and p-fluoroethylbenzene at 193 and 248 nm, J. Phys. Chem. A. 109, 4995 (2005).

28.  Cheng-Liang Huang, Chen-Lin Liu, Chi-Kung Ni, Jon T. Hougen, Electronic spectra of molecules with two C3V internal rotors: Torsional analysis of the A1Au–X1Ag LIF spectrum of biacetyl, J. Mol. Spectrosc. 233, 122 (2005).

29.  Ming-Fu Lin, Yuri A. Dyakov, Chien-Ming Tseng, Alexander M. Mebel, Sheng. Hsien. Lin, Yuan T. Lee, and Chi-Kung Ni, Photodissociation dynamics of pyridine, J. Chem. Phys. 123, 054309 (2005).

30.  Ming-Fu Lin, Chien-Ming Tseng, Yuan T. Lee, and Chi-Kung Ni, Photodissociation dynamics of indole in a molecular beam, J. Chem. Phys. 123, 124303 (2005).

31.  Chen-Lin Liu, Hsu Chen Hsu, Jia-Jia Lyu, and Chi-Kung Ni, Supercollisions and energy transfer of highly vibrationally excited molecules, J. Chem. Phys. 123, 131102 (2005)(communication).

32.  Yu. A. Dyakov, Chi-Kung Ni, Sheng Hsien Lin, Yuan T. Lee, Alexander M. Mebel, Photodissociation of Azulene at 193 nm: Ab Initio and RRKM Study, J. Phys. Chem. A. 109, 8774 (2005).

33.  Hsu Chen Hsu, Jia-Jia Lyu, Chen-Lin Liu, Cheng-Liang Huang, and Chi-Kung Ni, Generation and characterization of highly vibrationally excited molecular beam, J. Chem. Phys. 124, 054301 (2006).

34.  Chen-Lin Liu, Hsu Chen Hsu, Jia-Jia Lyu, and Chi-Kung Ni, Energy transfer of highly vibrationally excited azulene: collisions between azulene and krypton, J. Chem. Phys. 124, 054302 (2006).

35.  Chien-Ming Tseng, Yuri A. Dyakov, Cheng-Liang Huang, Yuan T. Lee, Sheng Hsien Lin, and Chi-Kung Ni, The role of seven-membered ring in the photoisomerization and photodissociation of small aromatic molecules, J. Chin. Chem. Soc. 53, 33 (2006).

36.  Hsu Chen Hsu, Chen-Lin Liu, Jia-Jia Lyu, and Chi-Kung Ni, Energy transfer of highly vibrationally excited azulene II: Photodissociation of azulene-Kr van der Waals clusters at 248 and 266 nm, J. Chem. Phys. 124, 134303 (2006).

37.  Ming-Fu Lin, Yuri A. Dyakov, Chien-Ming Tseng, Alexander M. Mebel, Sheng Hsien Lin, Yuan T. Lee, and Chi-Kung Ni, Photodissociation dynamics of pyrimidine, J. Chem. Phys. 124, 084303 (2006).

38.  Yu. A. Dyakov,A. M. Mebel, S. H. Lin,Y. T. Lee, and C.-K. Ni , Acetylene elimination in photodissociation of neutral azulene and its cation: An ab initio and RRKM Study, J. Chin. Chem. Soc. 53, 161 (2006).

39.  Yu. A. Dyakov, C.-K. Ni, S. H. Lin, Y. T. Lee, and A. M. Mebel, Ab initio and RRKM study of photodissociation of azulene cation, Phys. Chem. Chem. Phys. 8, 1404 (2006).

40.  V. Bernshtein, I. Oref, Chen-Lin Liu, Hsu Chen Hsu, Chi-Kung Ni, Experimental and computational investigation of energy transfer between azulene and krypton, Chem. Phys. Lett. 429, 317 (2006).

41.  Cheng-Liang Huang, Jyh-Chiang Jiang, Yuri A. Dyakov, Ming-Fu Lin, Chien-Ming Tseng, S. H. Lin, Yuan T. Lee, and Chi-Kung Ni, Photodissociation and photoisomerization of a-fluorotoluene and 4-fluorotoluene in a molecular beam, J. Chem. Phys. 125, 133305 (2006).

42.  Chen-Lin Liu, Hsu Chen Hsu, Jia-Jia Lyu, and Chi-Kung Ni, Energy transfer of highly vibrationally excited azulene III: Collisions between azulene and argon, J. Chem. Phys. (in press).

Book Chapters

"Multimass ion imaging, A new experimental technique and the application in photodissociation of small aromatic molecules,” Cheng-Liang Huang, Yuan T. Lee, and Chi-Kung Ni, in Modern Trends in Chemical Reaction dynamics: Experiment and Theory (Part II), K. Liu and X. Yang, Eds., World Scientific Publisher (2004).