The unimolecular dissociation of CH3OOH is investigated by exciting the molecule in the region of its 5νOH band and probing the resulting OH fragments using laser-induced fluorescence. The measured OH fragment rotational and translational energies are used to determine the CH3OOH bond dissociation energy, which we estimate to be 42.6±1kcalmol. Combining this value with the known heats of formation of the fragments also gives an estimate for the heat of formation of CH3OOH which at 0K we determine to be ΔHf0=27±1kcalmol. This experimental value is in good agreement with the results of ab initio calculations carried out at the CCSD(T)/complete basis set limit which finds the heat of formation of CH3OOH at 0K to be ΔHf0=27.3kcalmol.

1.
G. P.
Brasseur
,
J. J.
Orlando
, and
G. S.
Tyndall
,
Atmospheric Chemistry and Global Change
(
Oxford University Press
, New York,
1999
).
2.
L.
Jaeglé
,
D. J.
Jacob
,
W. H.
Brune
 et al,
J. Geophys. Res.
105
,
3877
(
2000
).
3.
M. J.
Prather
and
D. J.
Jacob
,
Geophys. Res. Lett.
24
,
3189
(
1997
).
4.
L.
Jaegle’
 et al,
Geophys. Res. Lett.
24
,
3181
(
1997
).
5.
F.
Ravetta
,
D. J.
Jacob
,
W. H.
Brune
 et al,
J. Geophys. Res.
106
,
32709
(
2001
).
6.
M. J.
Molina
and
G.
Arguello
,
Geophys. Res. Lett.
6
,
953
(
1979
).
7.
G. L.
Vaghijiani
and
A. R.
Ravishankara
,
J. Geophys. Res.
94
,
3487
(
1989
).
8.
G. L.
Vaghijiani
and
A. R.
Ravishankara
,
J. Chem. Phys.
92
,
996
(
1990
).
9.
M. A.
Thelen
,
P.
Felder
, and
J. R.
Huber
,
Chem. Phys. Lett.
213
,
275
(
1993
).
10.
S. W.
Novicki
and
R.
Vasudev
,
J. Chem. Phys.
93
,
8725
(
1990
).
11.
J.
Francisco
(unpublished).
12.
G.
Dutton
,
R. J.
Barnes
, and
A.
Sinha
,
J. Chem. Phys.
111
,
4976
(
1999
).
13.
G. L.
Vaghijiani
and
A. R.
Ravishankara
,
J. Phys. Chem.
93
,
7833
(
1989
).
14.
S. C.
Homitsky
,
S. M.
Dragulin
,
L. M.
Haynes
, and
S.
Hsieh
,
J. Phys. Chem. A
108
,
9492
(
2004
).
15.
B.
Ruscic
,
A. F.
Wagner
,
L. B.
Harding
 et al,
J. Phys. Chem. A
106
,
2727
(
2002
).
16.
D. L.
Osborn
,
D. J.
Leahy
, and
D. M.
Neumark
,
J. Phys. Chem. A
101
,
6583
(
1997
).
17.
M. J.
Frisch
,
G. W.
Trucks
,
H. B.
Schlegel
 et al, GAUSSIAN 03, Revision B.04, Gaussian, Inc., Wallingford, CT,
2004
.
18.
K.
Raghavachari
,
G. W.
Trucks
,
M.
Head-Gordon
, and
J. A.
Pople
,
Chem. Phys. Lett.
157
,
479
(
1989
).
19.
J. D.
Watts
,
J.
Gauss
, and
R.
Bartlett
,
J. Chem. Phys.
98
,
8718
(
1993
).
20.
T. H.
Dunning
, Jr.
,
J. Chem. Phys.
90
,
1007
(
1989
).
21.
R. A.
Kendall
,
T. H.
Dunning
, Jr.
, and
R. J.
Harrison
,
J. Chem. Phys.
96
,
6796
(
1992
).
22.
See EPAPS Document No. E-JCPSA6-122-016522 for the optimized geometry of CH3OOH and its corresponding rotational constants computed at the various levels of theory. This document can be reached via a direct link in the online article’s HTML reference section or via the EPAPS homepage (http://www.aip.org/pubservs/epaps.html).
23.
K. A.
Peterson
,
D. E.
Woon
, and
T. H.
Dunning
, Jr.
,
J. Chem. Phys.
100
,
7410
(
1994
).
24.
M. W.
Chase
, Jr.
,
J. Phys. Chem. Ref. Data Monogr.
9
,
1
(
1998
).
25.
S. P.
Sander
 et al,
Chemical Kinetics and Photochemical Data for Use in Stratospheric Modeling
, Evaluation 14 (
Jet Propulsion Laboratory
, Pasadena, CA,
2003
), JPL Publication 02-25.
26.
V. D.
Knyazev
and
I. R.
Slagle
,
J. Phys. Chem. A
102
,
1770
(
1998
).

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