1. (Kobe Univ. ) Takumi Nakano, Ryo Yamamoto, Shunji Kasahara
HIGH-RESOLUTION LASER SPECTROSCOPY OF S1-S0 TRANSITION OF NAPHTHALENE: MEASUREMENT OF VIBRATIONALLY EXCITED STATE
(Kobe Univ. ) Takumi Nakano, Ryo Yamamoto, Shunji Kasahara

2. Excited state dynamics
IVR
ISC
absorption
fluorescence
phosphorescence S0 S1 S2 T1
IC: Internal conversion
IVR: Intramolecular vibrational energy redistribution
ISC: Intersystem crossing
We observe the high-resolution spectrum to understand excited state dynamics.

3. Measurement of high-resolution spectrum
Rotational-resolved high-resolution spectrum in UV-VIS region
Assignments of rotational transitions
Regularity
of rotational lines
Molecular constants
in high accuracy
Anomalies
of rotational lines
 Line position (energy shift)
 Line width (broadening)
 Zeeman effect (splitting)
Molecular structure
Dynamical process

4. Fluorescence excitation spectrum of naphthalene
[1] D. L. Joo et al., J. Mol. Spectrosc. 215, 155 (2011)
[2] M. H. Kabir et al., J. Chem. Phys. 119, 3691 (2003)
[3] K. Yoshida et al., J. Chem. Phys. 130, (2009)
[4] M. Okubo et al., J. Chem. Phys. 116, 9293 (2002)
H. Kato et al., Bull. Chem. Soc. Jpn. 80, 456 (2007)
a type
b type
S1-S0
S2-S0
435 cm-1 [1,2]
1390 cm-1 [3]
1380 cm-1 [3]
2570 cm-1 [3]
0 – 0 [1]
32000
33000
34000
35000
36000
37000
1559 cm-1 [4]
Wavenumber / cm-1

5. Fluorescence excitation spectrum of naphthalene
2122
435
2570
1422
2867
1432
3068
S. M. Beck et al., J. Phys. Chem. 74, 43 (1981)
a type
b type
S1-S0
S2-S0
435 cm-1 [1,2]
1390 cm-1 [3]
1380 cm-1 [3]
1422 cm-1
1432 cm-1
2570 cm-1 [3]
2122 cm-1
3068 cm-1
2866 cm-1
0 – 0 [1]
32000
33000
34000
35000
36000
37000
1559 cm-1 [4]
Wavenumber / cm-1

6. I2 stabilized etalon marker
Experimental setup
Ar gas &
sample
Nd3+ :YVO4 laser
Ring dye laser
I2 stabilized etalon marker
I2 cell
Doubling cavity PM
pulsed nozzle
Vacuum chamber
liquid N2
trap
Photon counter
Computer
Magnet
Slit

7. Fluorescence excitation spectrum of naphthalene
2122
435
2570
1422
2867
1432
3068
S. M. Beck et al., J. Phys. Chem. 74, 43 (1981)
a type
b type
S1-S0
S2-S0
0 – 0
32000
33000
34000
35000
36000
37000
Wavenumber / cm-1

8. High-resolution spectrum of 0-0 band
32016
32015
32017
32018
32019
32020
32021
Obs.
Calc.(Trot = 40 K, G(FWHM) = cm-1 a-type)
Wavenumber / cm-1
Rotational lines were resolved

9. Molecular constants of 0-0 band
S0 (v = 0)
0-0 band
(previous work[1])
A / cm-1
(16)
(51)
(60) B
(27)
(74)
(31) C
(80)
(79)
(22) ΔK
1.87(32)×10-9 ―
1.82(11)×10-9
ΔJK
1.18(22)×10-9
1.751(55)×10-9 ΔJ
5.80(21)×10-10
5.704(80)×10-9 dK
1.37(17)×10-9
3.87(11)×10-9 dJ
1.59(10)×10-10
5.696(53)×10-10 T0
(3)
(2)
band type A
Assigned line
1043
3083
Std. Dev.
[1] D. L. Joo et al., J. Mol. Spectrosc. 215, 155 (2011)

10. High-resolution spectrum of 0-0 band
32016
32015
32017
32018
32019
32020
32021
Obs.
Calc.(Trot = 40 K, G(FWHM) = cm-1 a-type)
Wavenumber / cm-1

11. High-resolution spectrum of 0-0 band
qPK-
qPK+
J =33
J =32
J =31
Ka =1
Ka =0 32 31 30 2 1 31 30 29 3 2 30 29 28 4 3
Obs.
Calc.(40 K)
Wavenumber / cm-1

12. Zeeman effect of 0-0 band H = 0.49 T H = 0 T J = 35 34 33 32 31 30
Wavenumber/ cm-1

13. Zeeman splittings are small.
Zeeman effect of 0-0 band
Ka= 0 (Kc=J)
Zeeman Splitting / MHz J
Zeeman splittings are small.
Rotational quantum number dependence were found.
These effects are observed other vibronic bands.
H. Kato et al., Bull. Chem. Soc. Jpn. 80, 456 (2007)
M. Okubo et al., J. Chem. Phys. 116, 9293 (2002)
D. L. Joo et al., J. Mol. Spectrosc. 215, 155 (2011)

14. Fluorescence excitation spectrum of naphthalene
2122
435
2570
1422
2867
1432
3068
S. M. Beck et al., J. Phys. Chem. 74, 43 (1981)
a type
b type
S1-S0
S2-S0
2122 cm-1
32000
33000
34000
35000
36000
37000
Wavenumber / cm-1

15. High-resolution spectrum of 000 + 2122 cm-1 band
34140
34142
34144
34141
34143
34139
34145
Obs.
Calc.(Trot = 50 K, G(FWHM)= cm-1 b-type)
Wavenumber / cm-1

16. Molecular constants of vibronic bands
S0 (v = 0)
0-0 band
cm-1
A / cm-1
(16)
(60)
(47) B
(27)
(31)
(48) C
(80)
(22)
(84) ΔK
1.87(32)×10-9
1.82(11)×10-9 ―
ΔJK
1.18(22)×10-9
1.751(55)×10-9 ΔJ
5.80(21)×10-10
5.704(80)×10-9 dK
1.37(17)×10-9
3.87(11)×10-9 dJ
1.59(10)×10-10
5.696(53)×10-10 T0
(2)
(2)
band type A
Assigned line
3083
1232
Std. Dev.
0.0008

17. Energy shift of 000 + 2122 cm-1 band
Eob - Ecal

18. Energy shift of 000 + 2122 cm-1 band
Eob - Ecal
Eob - Ecal

19. Fluorescence excitation spectrum of naphthalene
2122
435
2570
1422
2867
1432
3068
S. M. Beck et al., J. Phys. Chem. 74, 43 (1981)
a type
b type
S1-S0
S2-S0
2866 cm-1
32000
33000
34000
35000
36000
37000
Wavenumber / cm-1

20. High-resolution spectrum of 000 + 2866 cm-1 band
34881
34882
34883
34884
34885
34886
Calc.(Trot = 10 K, G(FWHM) = cm-1 a-type)
Obs
Wavenumber / cm-1

21. Molecular constants of vibronic bands
S0 (v = 0)
0-0 band
cm-1
cm-1
A / cm-1
(16)
(60)
(47)
(10) B
(27)
(31)
(48)
(11) C
(80)
(22)
(84)
(51) ΔK
1.87(32)×10-9
1.82(11)×10-9 ―
ΔJK
1.18(22)×10-9
1.751(55)×10-9 ΔJ
5.80(21)×10-10
5.704(80)×10-9 dK
1.37(17)×10-9
3.87(11)×10-9 dJ
1.59(10)×10-10
5.696(53)×10-10 T0
(2)
(51)
(53)
band type A
Assigned line
3083
1232 90
Std. Dev.

22. High-resolution spectrum of 000 + 2866 cm-1 band
34881
34882
34883
34884
34885
34886
Calc.(Trot = 10 K, G(FWHM) = cm-1 a-type)
Obs
Wavenumber / cm-1

23. High-resolution spectrum of 000 + 2866 cm-1 band
Calc.(Trot = 10 K, G(FWHM) = cm-1 a-type)
Obs
Wavenumber / cm-1
- Rotational assignment: in progress
- Large background signal
- Energy shift?

24. Fluorescence excitation spectrum of naphthalene
2122
435
2570
1422
2867
1432
3068
S. M. Beck et al., J. Phys. Chem. 74, 43 (1981)
a type
b type
S1-S0
S2-S0
3068 cm-1
32000
33000
34000
35000
36000
37000
Wavenumber / cm-1

25. High-resolution spectrum of 000 + 3068 cm-1 band
35080
35081
35082
35083
35084
35085
Calc.(Trot = 10 K, G(FWHM) = cm-1 b-type)
Obs
Wavenumber / cm-1
- Large background signal
- Rotational assignment: difficult.

26. Rotational assignment
Summary
0-0
435 cm-1
2122 cm-1
2866 cm-1
3068 cm-1
Rotational assignment
done
In progress
Difficult
Energy shift
none
Several
Many?
Too　many?
Background
small
large
We determined molecular constants of 0-0 band.
The assign of cm-1 and cm-1 band are going on.
In the cm-1 band, energy shifts were observed.
Background signals of 2866cm-1 and 3068 cm-1 band are larger than lower vibrational state