The photophysics and photochemistry of benzene is a classic example of the richness of competing pathways available to a molecule after photoexcitation. Computer simulations are one way to provide a molecular picture for the dynamics behind the experimental observations. In this paper we develop a vibronic coupling Hamiltonian prepared in a previous paper [G. A. Worth, J. Photochem. Photobiol., A190, 190 (2007)]. Using CASPT2 we add dynamic correlation to the description of the excited states, improving their accuracy dramatically. Seven coupled states and all vibrational modes are included in the model and the parameters are obtained by fitting to points provided by the quantum chemistry calculations. The model is shown to be a good fit of the adiabatic surfaces and its accuracy is demonstrated by the calculation of three absorption bands, which compare favorably with the experimentally obtained spectra.

1.
Time-Dependent Methods for Quantum Dynamics
, edited by
K. C.
Kulander
(
Elsevier
,
Amsterdam
,
1991
).
2.
Dynamics of Molecules and Chemical Reactions
, edited by
R. E.
Wyatt
and
J. Z. H.
Zhang
(
Dekker
,
New York
,
1996
).
3.
R.
Kosloff
,
J. Phys. Chem.
92
,
2087
(
1988
).
4.
M. H.
Beck
,
A.
Jäckle
,
G. A.
Worth
, and
H. -D.
Meyer
,
Phys. Rep.
324
,
1
(
2000
).
5.
H.
Köppel
,
W.
Domcke
, and
L. S.
Cederbaum
,
Adv. Chem. Phys.
57
,
59
(
1984
).
6.
A.
Toniolo
,
A. L.
Thompson
, and
T.
Martinez
,
Chem. Phys.
304
,
133
(
2004
).
7.
I. J.
Palmer
,
I. N.
Ragazos
,
F.
Bernardi
,
M.
Olivucci
, and
M. A.
Robb
,
J. Am. Chem. Soc.
115
,
672
(
1993
).
8.
B. O.
Roos
,
K.
Andersson
, and
M. P.
Fülscher
,
Chem. Phys. Lett.
192
,
5
(
1992
).
9.
A.
Bernhardsson
,
N.
Forsberg
,
P. -Å.
Malmqvist
, and
B. O.
Roos
,
J. Chem. Phys.
112
,
2798
(
2000
).
10.
O.
Christiansen
,
J. F.
Stanton
, and
J.
Gauss
,
J. Chem. Phys.
108
,
3987
(
1998
).
11.
J.
Lorentzon
,
P.
Malmqvist
,
M.
Fülscher
, and
B. O.
Roos
,
Theor. Chim. Acta
91
,
91
(
1995
).
12.
L. T.
Scott
and
M.
Jones
, Jr.
,
Chem. Rev. (Washington, D.C.)
72
,
181
(
1972
).
13.
D.
Bryce-Smith
and
A.
Gilbert
,
Tetrahedron
32
,
1309
(
1972
).
14.
J.
Philis
,
A.
Bolovinos
,
G.
Andritsopoulos
,
E.
Pantos
, and
P.
Tsekeris
,
J. Phys. B
14
,
3621
(
1981
).
15.
C. S.
Parmenter
,
Adv. Chem. Phys.
22
,
365
(
1972
).
16.
M.
Clara
,
T.
Hellerer
, and
H. J.
Neusser
,
Appl. Phys. B: Lasers Opt.
71
,
431
(
2000
).
17.
E. N.
Lassettre
,
A.
Skerbele
,
M. A.
Dillon
, and
K. J.
Ross
,
J. Chem. Phys.
48
,
5066
(
1968
).
18.
J. H.
Callomon
,
T. M.
Dunn
, and
I. M.
Mills
,
Chem. Phys. Lett.
165
,
443
(
1990
).
19.
A.
Sobolewski
,
C.
Woywod
, and
W.
Domcke
,
J. Chem. Phys.
98
,
5627
(
1993
).
20.
W.
Radloff
,
T.
Freudenberg
,
H. -H.
Ritze
,
V.
Stert
,
K.
Weyers
, and
F.
Noack
,
Chem. Phys. Lett.
245
,
400
(
1995
).
21.
G. A.
Worth
,
J. Photochem. Photobiol., A
190
,
190
(
2007
).
22.
B.
Roos
,
P.
Linse
,
P.
Siegbahn
, and
M.
Blomberg
,
Chem. Phys.
66
,
197
(
1982
).
23.
G. A.
Worth
and
L. S.
Cederbaum
,
Annu. Rev. Phys. Chem.
55
,
127
(
2004
).
24.
G. A.
Worth
,
H. -D.
Meyer
, and
L.
Cederbaum
, in
Conical Intersections: Electronic Structure, Dynamics and Spectroscopy
, edited by
W.
Domcke
,
D.
Yarkony
, and
H.
Köppel
(
World Scientific
,
Singapore
,
2004
), pp.
583
617
.
25.
M.
Döscher
,
H.
Köppel
, and
P. G.
Szalay
,
J. Chem. Phys.
117
,
2645
(
2002
).
26.
H.
Köppel
,
M.
Döscher
,
I.
Bâldea
,
H. -D.
Meyer
, and
P. G.
Szalay
,
J. Chem. Phys.
117
,
2657
(
2002
).
27.
H. -D.
Meyer
,
U.
Manthe
, and
L. S.
Cederbaum
,
Chem. Phys. Lett.
165
,
73
(
1990
).
28.
L. S.
Cederbaum
,
W.
Domcke
,
H.
Köppel
, and
W.
von Niessen
,
Chem. Phys.
26
,
169
(
1977
).
29.
L. S.
Cederbaum
,
H.
Köppel
, and
W.
Domcke
,
Int. J. Quantum Chem.
15
,
251
(
1981
).
30.
W.
Eisfeld
and
A.
Viel
,
J. Chem. Phys.
122
,
4603
(
2004
).
31.
A.
Markmann
,
G. A.
Worth
, and
L. S.
Cederbaum
,
J. Chem. Phys.
122
,
144320
(
2005
).
32.
B.
Lasorne
,
F.
Sicilia
,
M. J.
Bearpark
,
M. A.
Robb
,
G. A.
Worth
, and
L.
Blancafort
,
J. Chem. Phys.
128
,
124307
(
2008
).
33.
G. A.
Worth
,
M. H.
Beck
,
A.
Jäckle
, and
H. -D.
Meyer
, The MCTDH Package, Version 8.3, see http://www.pci.uni-heidelberg.de/tc/usr/mctdh/ (
2003
).
34.
C.
Cattarius
,
G. A.
Worth
,
H. -D.
Meyer
, and
L. S.
Cederbaum
,
J. Chem. Phys.
115
,
2088
(
2001
).
35.
G. A.
Worth
,
G.
Welch
, and
M. J.
Paterson
,
Mol. Phys.
104
,
1095
(
2006
).
36.
H. -J.
Werner
and
P.
Knowles
,
MOLPRO, Version 2006.1
(
University of Birmingham
,
U.K.
,
2006
).
37.
Multidimensional Quantum Dynamics: MCTDH Theory and Applications
, edited by
H. -D.
Meyer
,
F.
Gatti
, and
G. A.
Worth
(
Wiley
,
London
,
2009
).
38.
See EPAPS supplementary material at http://dx.doi.org/10.1063/1.3197555 for details of the parameters not included in the paper.
39.
M. J.
Frisch
,
G. W.
Trucks
, and
H. B.
Schlegel
 et al, GAUSSIAN03, Revision C.02, Gaussian, Inc., Pittsburgh PA,
2003
.
40.
L.
Goodman
,
A. G.
Ozkabak
, and
A. N.
Thakur
,
J. Phys. Chem.
95
,
9044
(
1991
).

Supplementary Material

You do not currently have access to this content.