Vibrationally Mediated Bimolecular Reactions

Christopher J. Annesley University of Wisconsin - Madison

Comparing Reactivities of Different Vibrational States in

CH3D

Christopher J. Annesley University of Wisconsin - Madison

How do vibrations affect reactions?

How do vibrations affect reactions?

How do vibrations affect reactions?

CH3D(1 or 4) + Cl

S. Yoon, R. Holiday, E. Sibert III, and F. Crim J. Chem. Phys. 119, 9568 (2003)

CH3D(1 or 4) + Cl

S. Yoon, R. Holiday, E. Sibert III, and F. Crim J. Chem. Phys. 119, 9568 (2003)

1.74

1

44

11

4

1

)32(06.0)52(64.0)1(77.01

'''

fR

fR

AbsorptionAction

AbsorptionAction

R

R

RAbsorptionAction

II

II

II

Antisymmetric Stretch, 4

Symmetric Stretch, 1

CH3D(1 or 4) + Cl

Antisymmetric Stretch, 4

Symmetric Stretch, 1

CH3D(1 or 4) + Cl

Antisymmetric Stretch, 4

Symmetric Stretch, 1

CH3D(1 or 4) + Cl

Antisymmetric Stretch, 4

Symmetric Stretch, 1

CH3D(1 or 4) + Cl

Antisymmetric Stretch, 4

Symmetric Stretch, 1

CH3D(1 or 4) + Cl

Product Distributions

Action Spectra

C. Annesley, A. Berke and F. F. Crim J. Phys. Chem. A submitted

Fitting constants

Lutz, B. L.; De Bergh, C.; Maillard, J. P. Astrophysical Journal 1983, 273, 397.

Action spectra

CH3D(ν) + Cl

Holiday, R. J.; Kwon, C. H.; Annesley, C. J.; Crim, F. F. J. Chem. Phys. 2006, 125, 133101.

CH3D(ν) + Cl

5.00.2535353 01000100

02000200

0100

0200

AbsorptionAction

EAbsorption

EAction

R

ER

II

II

05.000.111001100

11001100

1100

1100 111

E

AbsorptionE

Action

AAbsorption

AAction

ER

AR

II

II

Holiday, R. J.; Kwon, C. H.; Annesley, C. J.; Crim, F. F. J. Chem. Phys. 2006, 125, 133101.

State Mixing?

Aexp Acalc Bexp Bcalc ζexp ζcalc

ν1+ν2 5.174 5.157 3.860 3.790

ν2+ν4 5.223 5.203 3.803 3.788 0.084 .241

ν2+2ν5 5.251 5.274 3.990 3.843

Herzberg, G. Molecular Spectra and Molecular Structure: II. Infrared and Raman Spectraof Polyatomic Molecules; Van Nostrand Reinhold Co.: New York, 1945.

Summary

• Different vibrations react differently– Products

• Spectator model

– Reactivities

• Highly mixed states obscure these differences

• Need new systems to find more examples CH3F, CH2F2

Thanks

• NSF