IAMS, Academia Sinica, Taiwan, 台灣 中研院原分所 Course: Molecular Spectroscopy Taiwan International Graduate Program (TIGP) Professor: Wen-Bih Tzeng, Lab: 108, Office: 301 ： website ： lectures on electronic spectroscopy of molecules in the gas phase Tuesday 9:10-12:00, 2013/2/ /3/5 (Classroom: 311) Suggested books (NTU Chemistry Library): 1. Modern Spectroscopy, 4th ed. by J. Michael Hollas, John Wiley & Sons, Molecular Spectra and Molecular Structure, G. Herzberg, D. van Nostrand Company, Inc., QC 451.H463v

Lecture Planning Date 2013/02/19 (Tue)Introduction Some Important Results in Quantum Mechanics Electromagnetic Radiation and its Interaction with Atoms and Molecules (Chapter 1) 2013/02/26 (Tue)Electromagnetic Radiation and its Interaction with Atoms and Molecules (Chapter 2) Electronic spectroscopy (Chapter 7) 2013/03/05 (Tue)Photoelectron spectroscopy and related spectroscopies (REMPI, ZEKE, MATI spectroscopy)

Energy Levels

wbt5 Resonant two-photon (R2PI) and mass-analyzed threshold ionization (MATI) processes electronic excitation ionization

Preparation of C 6 H 5 NHD and C 6 H 5 ND 2 (Mass 93) (Mass 95) (Mass 94)

Preparation of C 6 D 5 NHD and C 6 D 5 ND 2 (Mass 100) (Mass 98) (Mass 99)

Relative Intensity Mass / amu TOF spectra of deuterium substituted aniline isotopomers λ = nm λ = nm λ = nm 93 ↔ C 6 H 5 NH ↔ C 6 H 5 NHD + 98 ↔ C 6 D 5 NH ↔ C 6 D 5 NHD ↔ C 6 D 5 ND 2 +

One photon energy / cm -1 Relative Intensity (a) C 6 H 5 NH 2 (b) C 6 H 5 NHD (b) C 6 H 5 ND 2 Vibronic spectra of deuterium substituted aniline isotopomers

Relative Wavenumber / cm -1 Relative Intensity (a) C 6 D 5 NH 2 (b) C 6 D 5 NHD (c) C 6 D 5 ND 2

MATI spectra of deuterium substituted aniline isotopomers Ion Internal Energy / cm -1 Relative Intensity via S cm cm cm -1 (a) C 6 H 5 NH 2 (b) C 6 H 5 NHD (c) C 6 H 5 ND 2

Ion Internal Energy / cm -1 Relative Intensity via S cm cm cm -1 (a) C 6 D 5 NH 2 (b) C 6 D 5 NHD (c) C 6 D 5 ND 2 MATI spectra of deuterium substituted aniline isotopomers

13 Vibronic spectra of m-, o-, p-fluoroaniline by 1C-R2PI

14 Vibronic spectra of m-, o-, p-fluoroaniline by 1C-R2PI

15 Vibronic spectrum of m- and o-fluoroaniline mixture

16 MATI spectra of m-, o-, p-fluoroaniline m-fluoroaniline NIST: 8.32 － 8.33 eV MATI: ± eV o-fluoroaniline NIST: 8.2 － 8.5 eV MATI: ± eV p-fluoroaniline NIST: 7.9 － 8.2 eV MATI: ± eV

17 Vibronic spectra of m-, o-, p-fluoroanisole m-fluoroanisole has cis and trans rotamers.

18 MATI spectra of m-, o-, p-fluoroanisole trans-m-fluoroanisole NIST: 8.4 － 8.7 eV MATI: ± eV cis-m-fluoroanisole NIST: 8.4 － 8.7 eV MATI: ± eV o-fluoroanisole NIST: － MATI: ± eV p-fluoroanisole NIST: 8.3 － 8.6 eV MATI: ± eV

IR and REMPI spectra of guanine Ref: (a) IR: Delabar et al., Spectrochim Acta 34A, 129 (1978). (b) REMPI: de Vries and coworkers, JACS 121, 4896 (1999).

Possible structures of guanine (c) (b)(a) Ref: de Vries and coworkers, JCP 115, 4606 (2001).

REMPI spectrum of guanine Ref: SC Yang, JL Lin, Lab 108, IAMS

REMPI spectrum of guanine Ref: SC Yang, JL Lin, Lab 108, IAMS MP2/6-311G(d,p): a=7H-Keto, 1 kJ/mol b=9H-Keto, 4 kJ/mol c=9H-Enol, 0 kJ/mol

REMPI spectrum of guanine Ref: SC Yang, JL Lin, Lab 108, IAMS MP2/6-311G(d,p): a=7H-Keto, 1 kJ/mol b=9H-Keto, 4 kJ/mol c=9H-Enol, 0 kJ/mol