1

N. NISHIMIYA and T. YUKIYA

Tokyo Polytechnic University, Kanagawa, JAPAN.

HIGH – RESOLUTION LASER SPECTROSCOPY OF THE A3Π1 ← X 1Σ+ SYSTEM OF ICl

IN 0.8 m REGION

2

Our Research

Laser spectroscopy of electronic band system of halide molecules. Target: ICl, IBr, I2, and Br2 For establishing the frequency standard in the near infrared region. In this time we have measured the A-X spectra of ICl in the region of

11300-14450 cm-1 region. ICl spectrum is weak comparing to other halogen molecules. It is easy to assign, because of its wide spectrum intervals. One spectrum at least can be found within a continuous tuning range of a

titanium sapphire laser in the 0.8 m region. The constants have determined by taking into consideration isotopic r

educed mass ratio.

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References(1) J.A.Coxon,et. al. ,``The A31u 　 X1+ Absorption Spectrum of ICl. '', J.Mol.Spectrosc.79,

363 (1980)

(2) J.A.Coxon and M.A.Wickramaaratchi,``The A31 　 X1+ Emission Spectrum of ICl in the Near Infrared. '', J.Mol.Spectrosc.79, 380 (1980)

(3) J.C.DBrand and A.R.Hoy,``High Vibrational Level of the the X state of ICl, and the Electronic-Coriolis Coupling of the X and A states.'',J.Mol.Spectroscopy, 114, 197 (1985)

(4) J.C.D.Brand, et.al. ``The A’(32) of ICl”, J.Mol.Spectrosc., 113, 388 (1985)

(5) H.G.Hedderich, et.al.,``The High-Resolution Infrared Spectrum of Iodine Monochloride.'', J.Mol.Spectrosc., 155, 384 (1992).

(6) C.M.Western, ``Variation of the electronic wave function with internuclear separation: High-resolution spectroscopy of the A3 state of I35Cl near the dissociation limit.’’, J.Chem.Phys., 98, 1826 (1993)

(7) T.J.Slotterback, et.al.,``Hyperfine measurements in the X and B electronic states of I35,37Cl: Probing the ionic character of the chemical bond.'', J.Chem.Phys., 101, 7221(1994)

(8) T.J.Slotterback, et.al.,``Hyperfine analysis of the mixed A31 v=28 and X1+ v=69 states of I35Cl”, J.Chem.Phys., 103, 9125(1994)

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J+1(odd)

+

f-levele-level

J=0Q

Type doubling

J=-1P

J=1RJ(even)

Energy

Internuclear distance r

J+1(odd)

J(even)

-

e-levelf-level

-+

+-

Potential Energy

P and R line shape

5

15Hz

400 MHzFrequency Modulation:Saturated Vapor at Room Temp.Cell Temperature and Gas Pressure:

14.4mOptical Path Length:

Conditions

Lock in Amp.

Lock in Amp.

Wave MeterOpt. Fiber

GeneratorFunction

PC

BusLocal

M

M

BS

BS

BS

Lock in Amp.

M

Ti:Al2O3Laser

ControllerLaser

Sweep signal

Etalon Driven Signal

BRF Driven Signal D/AServo Amp.

Ar+ Ion Laser

BS

Confocal Cavity

Power MonitorPD

PD

GP-IB Bus

PDAbsorption Cell (White Cell)

L

Osc.

Block Diagram of The Ti:Sapphire Ring Laser Spectrometer.

6

Recorder Trace of the Absorption Lines in 12600 cm-1 Region

7

Fortrat Diagram of I35Cl

1 2 3 4 50 6 7

12345

0

67II3535ClCl

v’v’

v”v”P,Q,R-Blanches

Only Q-Blanches

v”v”

0

3 5 7 7

4

3

4

4

10 0 0

cm-1

8

II3535ClCl v’=0-7T’0 ,T’1 , ,T’7B’0e ,B’1e , ,B’7e

B’0f ,B’1f , ,B’7f

D’0 ,D’1 , ,D’7H’0 ,H’1 , ,H’7

II3535ClCl v’=0-7T’0 ,T’1 , ,T’7B’0e ,B’1e , ,B’7e

B’0f ,B’1f , ,B’7f

D’0 ,D’1 , ,D’7H’0 ,H’1 , ,H’7

II3737ClCl v’=0-6T’0 ,T’1 , ,T’6B’0e ,B’1e , ,B’6e

B’0f ,B’1f , ,B’6f

D’0 ,D’1 , ,D’6H’0 ,H’1 , ,H’6

II3737ClCl v’=0-6T’0 ,T’1 , ,T’6B’0e ,B’1e , ,B’6e

B’0f ,B’1f , ,B’6f

D’0 ,D’1 , ,D’6H’0 ,H’1 , ,H’6II3535Cl / ICl / I3737ClCl

Y10’’ , Y20’’ , Y30’’Y01’’, Y11’’ , Y21’’

Y02’’, Y12’’ Y03’’, Y13’’

II3535Cl / ICl / I3737ClClY10’’ , Y20’’ , Y30’’Y01’’, Y11’’ , Y21’’

Y02’’, Y12’’ Y03’’, Y13’’

0 0)2/(

,,

32222/

)1(2

1

)1()1()1(

l

m

m

l

lmml

ml

vvfvevvJ

JJvY

Y

JJHJJDJJBTE

The Coefficients of the Power Expansion for the A and the X State

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The Spectroscopic Constants of The X State

In cm-1 and 2.5 in parentheses=0.0022 cm-1

Y’’10 384.29416 Y’’01 0.114157656

=0.0021 cm-1

1)

Type B( constrain Y’’10 and Y’’01)

Type A(All parameter is variable.)

H.G.Heddrich and P.F.Bernath ,J.Mol.Spectrosc.155.384-392(1992)

=0.0022 cm-1

2) Y’’03 is calculated using 152

1,0

0,11,14

0,1

51,0

3,0 107243.816

316

Y

YY

Y

YY

Type C( constrain Y’’10, Y’’01 and Y’’03)

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The Spectroscopic Constants of The A State

II3535ClCl

II3737ClCl

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Relationship between Tv and Vibrational Level

13800

14000

14200

14400

14600

14800

15000

15200

0 1 2 3 4 5 6 7

T’v

v

II3737ClClII3535ClCl

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Deviation of Tv from the (v+1/2) Polynomial

-0.165

-0.160

-0.155

-0.150

-0.145

-0.140

-0.135

-0.130

-0.125

-0.120

0 1 2 3 4

II3535ClCl

II3737ClClTv

v

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Relationship between Bvf and Qv and Vibrational Level

0.076

0.078

0.080

0.082

0.084

0 1 2 3 4 5 6 7

B’vf

v

II3535ClCl

II3737ClCl0.80

0.90

1.00

1.10

1.20

1.30

0 1 2 3 4 5 6

Qv x 105

II3737ClCl

II3535ClCl

v

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Relationship between Dv and Hv and Vibrational Level

4.55.05.56.06.57.07.58.0

0 1 2 3 4 5 6 7

D’v x108

II3535ClCl

II3737ClCl

v-4.0-3.5-3.0-2.5-2.0-1.5-1.0-0.50.0

0 1 2 3 4 5 6 7

H’v x1013

II3535ClCl

II3737ClCl

v

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Average Line Splittings of Vibrational Level in the P- and R-Branches

0.000

0.005

0.010

0.015

0.020

0.025

0.030

0.035

0.040

0 1 2 3 4 5 6

0.0317cm-1

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Summary

A – X system of P,Q,R-branch lines were assigned. 4900 lines

X-state of Dunham coefficients were determined by using a mass-reduced least square fitting procedure. 7 parameters

Spectroscopic constants of A-state were calculated . Tv, Bvf, qv, Dv, Hv for each vibrational levels (Dunham coefficients are not suitable for A- state.)