Eirík´s project(?) CH3I: agust,www,...rempi/ch3i/PPT-050112ak.ppt ( ).
REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin...
-
Upload
ursula-turner -
Category
Documents
-
view
229 -
download
1
Transcript of REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin...
![Page 1: REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin Kim, and Hyuk KANG Ajou University, Suwon 443-749, Korea.](https://reader036.fdocuments.net/reader036/viewer/2022062421/56649d8b5503460f94a718cf/html5/thumbnails/1.jpg)
REMPI and Double Resonance Spectroscopy of
L-β-Homotryptophan in Gas Phase
Hae Jun Jung, Jung Jin Kim, and Hyuk KANGAjou University, Suwon 443-749, Korea
69th International Symposium on Molecular Spectroscopy
![Page 2: REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin Kim, and Hyuk KANG Ajou University, Suwon 443-749, Korea.](https://reader036.fdocuments.net/reader036/viewer/2022062421/56649d8b5503460f94a718cf/html5/thumbnails/2.jpg)
Submicroscopic Histology
• Section the active part• Use a natural chromophore or stain it• Freeze it• Illuminate it with laser in a vacuum chamber• Directly observe the active conformations• Directly observe the active molecular interaction
![Page 3: REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin Kim, and Hyuk KANG Ajou University, Suwon 443-749, Korea.](https://reader036.fdocuments.net/reader036/viewer/2022062421/56649d8b5503460f94a718cf/html5/thumbnails/3.jpg)
How to Distinguish Conformers w/ UV
Conformer A
Conformer B
S0
S1
hνA0-0 hνB0-0hνA0-0 < hνB0-0
0.319 kcal mol-1 (B3LYP/6-31G**)
cis-meta-aminophenol
trans-meta-aminophenol
![Page 4: REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin Kim, and Hyuk KANG Ajou University, Suwon 443-749, Korea.](https://reader036.fdocuments.net/reader036/viewer/2022062421/56649d8b5503460f94a718cf/html5/thumbnails/4.jpg)
S1
S0
hνburn
c-3AP
t-3AP
UV-UV Double ResonanceUV-UV Hole Burning
hνprobe
Mass-Resolved Conformer-Specific UV Spectrum
![Page 5: REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin Kim, and Hyuk KANG Ajou University, Suwon 443-749, Korea.](https://reader036.fdocuments.net/reader036/viewer/2022062421/56649d8b5503460f94a718cf/html5/thumbnails/5.jpg)
L-β-homotryptophan
L-tryptophan
E. E. Baquero, W. H. James, III, S. H. Choi, S. H. Gellman, and T. S. Zwier, J. Am. Chem. Soc., 130, 4784 (2008).
more flexible or easier to fold?
β-Amino acids
![Page 6: REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin Kim, and Hyuk KANG Ajou University, Suwon 443-749, Korea.](https://reader036.fdocuments.net/reader036/viewer/2022062421/56649d8b5503460f94a718cf/html5/thumbnails/6.jpg)
L. C. Snoek, R. T. Kroemer, M. R. Hockridge and J. P. Simons, Phys. Chem. Chem. Phys., 3, 1819 (2001).
Conformers of tryptophan
![Page 7: REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin Kim, and Hyuk KANG Ajou University, Suwon 443-749, Korea.](https://reader036.fdocuments.net/reader036/viewer/2022062421/56649d8b5503460f94a718cf/html5/thumbnails/7.jpg)
Experimental and Computational
• Thermal oven / laser desorption• Supersonic expansion• Frequency doubled pulsed dye laser• Resonance-Enhanced
Multiphoton Ionization(REMPI)
• TOF MS, MCP, DSO, PC
• Conformational search – Macromodel with Amber force field
• Geometry optimization – Gaussian09 at M05-2X/6-31G**
LinearTOF
MCP
DiffusionPump
DiffusionPump
TurboPump
IG
NY-61 Nd:YAGLaser (532nm)
ND-60 TunableDye Laser Autotracker(BBO)
PVSkimmer
SC
DM
![Page 8: REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin Kim, and Hyuk KANG Ajou University, Suwon 443-749, Korea.](https://reader036.fdocuments.net/reader036/viewer/2022062421/56649d8b5503460f94a718cf/html5/thumbnails/8.jpg)
34800 34900 35000 35100 35200
Sig
na
l (A
.U)
Wavenumber (cm-1)
REMPI spectrum of laser-desorbed Trp
T. R. Rizzo, Y. D. Park, L. A. Peteanu, and D. H. Levy, J. Chem. Phys. 84, 2534 (1986).
Levy’s group
Ours
![Page 9: REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin Kim, and Hyuk KANG Ajou University, Suwon 443-749, Korea.](https://reader036.fdocuments.net/reader036/viewer/2022062421/56649d8b5503460f94a718cf/html5/thumbnails/9.jpg)
REMPI spectrum of Trp and Trp-HCl
R-NH3+ + Cl-
R-NH2 + HCl
R-NH3+·Cl-
34860 34880 34900 34920
Sig
nal (
A.U
.)
Wavenumber (cm-1)
Trp Trp HCl
22 24 26 28 30 32 34-0.18
-0.16
-0.14
-0.12
-0.10
-0.08
-0.06
-0.04
-0.02
0.00
0.02
0.04
Mas
s S
igna
l (m
V)
Flight time (us)
Trp Trp HCl
![Page 10: REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin Kim, and Hyuk KANG Ajou University, Suwon 443-749, Korea.](https://reader036.fdocuments.net/reader036/viewer/2022062421/56649d8b5503460f94a718cf/html5/thumbnails/10.jpg)
34600 34700 34800 34900 35000 35100 35200 35300 35400
Ion S
ignal (A
.U.)
Wavenumber (cm-1)
34750 34800 34850 34900 34950 35000 35050
Ion
Sig
nal (
A.U
.)
Wavenumber (cm-1)
REMPI spectrum of L-β-homotryptophan*
*HCl salt
![Page 11: REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin Kim, and Hyuk KANG Ajou University, Suwon 443-749, Korea.](https://reader036.fdocuments.net/reader036/viewer/2022062421/56649d8b5503460f94a718cf/html5/thumbnails/11.jpg)
34600 34700 34800 34900 35000 35100 35200 35300 35400
34600 34700 34800 34900 35000 35100 35200 35300 35400
Ion S
ignal (A
.U.)
Wavenumber (cm-1)
L-β-Homotryptophan and L-tryptophan
*HCl salt
![Page 12: REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin Kim, and Hyuk KANG Ajou University, Suwon 443-749, Korea.](https://reader036.fdocuments.net/reader036/viewer/2022062421/56649d8b5503460f94a718cf/html5/thumbnails/12.jpg)
UV-UV HB spectra of L-β-hTrp
34800 34850 34900 34950 35000 35050
Sig
nal (
A.U
.)
Wavenumber / cm-1
H.B. at 34980 cm-1
H.B. at 34950 cm-1
REMPI
*
*
![Page 13: REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin Kim, and Hyuk KANG Ajou University, Suwon 443-749, Korea.](https://reader036.fdocuments.net/reader036/viewer/2022062421/56649d8b5503460f94a718cf/html5/thumbnails/13.jpg)
0
1
2
3
4
5
6
Re
lativ
e e
ne
rgy
(kJ/
mo
l)
0.0 kJ/mol
3.66 kJ/mol
0.86 kJ/mol
3.64 kJ/mol(23% at 300 K)
4.76 kJ/mol
0.22 kJ/mol 0.28 kJ/mol
2.10 kJ/mol
5.66 kJ/mol(10% at 300K)
2.59 kJ/mol
1.82 kJ/mol(48% at 300 K)
2.61 kJ/mol2.80 kJ/mol
4.36 kJ/mol
5.16 kJ/mol
Stable conformers of L-β-homotryptophan
M05-2X/6-31G**
![Page 14: REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin Kim, and Hyuk KANG Ajou University, Suwon 443-749, Korea.](https://reader036.fdocuments.net/reader036/viewer/2022062421/56649d8b5503460f94a718cf/html5/thumbnails/14.jpg)
Issues
• Short progression– Lower Franck-Condon activity than Trp?– Faster non-radiative process?
• Less conformers observed– Signal intensity ≠ population– Low barriers between conformers
• Conformer-specific non-radiative process?
L-β-homotryptophanL-tryptophan
![Page 15: REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin Kim, and Hyuk KANG Ajou University, Suwon 443-749, Korea.](https://reader036.fdocuments.net/reader036/viewer/2022062421/56649d8b5503460f94a718cf/html5/thumbnails/15.jpg)
Conformer-specific IC
M. Mališ, Y. Loquais, E. Gloaguen, C. Jouvet, V. Brenner, M. Mons, I. Ljubić and N. Došlić, Phys. Chem. Chem. Phys. 16, 2285 (2014).
![Page 16: REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin Kim, and Hyuk KANG Ajou University, Suwon 443-749, Korea.](https://reader036.fdocuments.net/reader036/viewer/2022062421/56649d8b5503460f94a718cf/html5/thumbnails/16.jpg)
Published in: Momir Mališ; Yohan Loquais; Eric Gloaguen; Himansu S. Biswal; François Piuzzi; Benjamin Tardivel; Valérie Brenner; Michel Broquier; Christophe Jouvet; Michel Mons; Nađa Došlić; Ivan Ljubić; J. Am. Chem. Soc. 2012, 134, 20340-20351.DOI: 10.1021/ja3054942Copyright © 2012 American Chemical Society
![Page 17: REMPI and Double Resonance Spectroscopy of L -β-Homotryptophan in Gas Phase Hae Jun Jung, Jung Jin Kim, and Hyuk KANG Ajou University, Suwon 443-749, Korea.](https://reader036.fdocuments.net/reader036/viewer/2022062421/56649d8b5503460f94a718cf/html5/thumbnails/17.jpg)
Acknowledgements
• Hae Jun Jung• Jung Jin Kim