A look at the dissociation pathways
of Acetone and Trifluoro Acetone
By
Smriti Anand
and
Muhannad Zamari
Outline
Introduction
 Systems Studied
 Calculations
 Results and Discussions
 Future Work
 Acknowledgements

Introduction

Previous Work


Dissociation of molecules in an intense laser
field
What is our interest?

Other fragments ?????
 Pathways for the dissociation ???
Systems of Interest

Molecules studied:

Acetone

Trifluoro Acetone
Acetone


Neutral
Radical Cation
Trifluoro Acetone


Neutral
Radical Cation
Possible fragments ???

Acetone:
Radicals, anions, and cations of CH3 and
CH3CO.
 CO ????


Trifluoro Acetone
Radicals, anions, and cations of CH3, CF3,
CH3CO, CF3CO.
 CO ????

Energetics (Neutral molecule)
at HF/3-21G
Energetics (Radical cation)
at HF/3-21G
Rigid Vs Relaxed Scan along C-CH3 in
Acetone at HF/3-21G
-190.44
0
1
2
3
4
5
-190.46
Energy/ Hartrees
-190.48
-190.5
Rigid Scan
Relaxed Scan
-190.52
-190.54
-190.56
-190.58
-190.6
C-CH3 bond length/ A o
Rigid Vs Relaxed Scan along C-CF3 bond
in Trifluoro Acetone at HF/3-21G
-485.38
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
-485.4
Energy/ Hartrees
-485.42
-485.44
Rigid Scan
Relaxed Scan
-485.46
-485.48
-485.5
-485.52
C-CF3 bond length/ Ao
Rigid Vs Relaxed Scan along C-CH3
bond in Trifluoro Acetone at HF/3-21G
-485.32
-485.34 0
1
2
3
4
5
Energy/ Hartrees
-485.36
-485.38
-485.4
-485.42
Rigid scan
Relaxed Scan
-485.44
-485.46
-485.48
-485.5
-485.52
C-CH3 bond length/ Ao
Transition State
(Trifluoro Acetone)
Transition State (Acetone)
Future Work




Trajectory Calculations.
Branching ratios of the various
pathways ?
CH3COCF3 ---- > COCF3 + CH3
---- > COCH3 + CF3
---- > CH3 + CF3 + CO
CH3COCH3 ---- > CH3CO + CH3
---- > CH3 + CH3 + CO
Future Work




Other fragments ???
Possibility of Rearrangement ??
Further studies at a higher level of
theory
Study other molecules.
Acknowledgments





Thanks to:
Dr. Schlegel
Dr. Levis
Noel Moore (Levis Group)
Xiaosong Li (Schlegel Group)
CH3CO and CF3CO Radicals
CH3CO Cation
CF3CO Cation
CH3 and CF3 radicals
CH3 and CF3 cations