The 2 3A′′−3 3A′′ and the 1 1A′′−2 1A′′ seams of conical intersection in CH2 and H2S, respectively, are considered. The nuclear coordinate dependence of the seam of conical intersection, the energy of the lower adiabatic potential energy surface along closed loops containing the conical intersection, and the nonremovable part of the derivative coupling in the region contained within the closed loops are studied. The energetics and derivative couplings in the vicinity of the conical intersections are analyzed in terms of the characteristic parameters of a conical intersection, determined at the configuration interaction level using analytic gradient techniques. The characteristic parameters are found to predict, in a qualitative manner, the energetics at moderate distances from the conical intersection. Loops containing the conical intersection that exhibit and do not exhibit the geometric phase effect are considered. An unusual trifurcation of the C2v seam of conical intersection in CH2 into a C2v branch and 2Cs branches is discovered. For H2S, over the range of nuclear coordinates considered, only points of conical intersection with C2v symmetry were found.

1.
D. R.
Yarkony
,
Rev. Mod. Phys.
68
,
985
(
1996
).
2.
R. A.
Beärda
,
M. C.
van Hemert
, and
E. F.
van Dishoeck
,
J. Chem. Phys.
97
,
8240
(
1992
).
3.
R. A.
Beärda
,
G.-J.
Kroes
,
M. C.
van Hemert
,
B.
Heumann
,
R.
Schinke
, and
E. F.
van Dishoeck
,
J. Chem. Phys.
100
,
1113
(
1994
).
4.
R. A.
Beärda
,
M. C.
van Hemert
, and
E. F.
van Dishoeck
,
J. Chem. Phys.
102
,
8930
(
1995
).
5.
G.-J.
Kroes
,
M. C.
van Hemert
,
R. A.
Beärda
, and
E. F.
van Dishoeck
,
J. Chem. Phys.
99
,
228
(
1993
).
6.
R. N.
Dixon
,
C. C.
Marston
, and
G. G.
Balint-Kurti
,
J. Chem. Phys.
93
,
6520
(
1990
).
7.
G.
Theodorakopoulos
and
I. D.
Petsakalais
,
Chem. Phys. Lett.
178
,
475
(
1991
).
8.
K.
Weide
,
V.
Staemmler
, and
R.
Schinke
,
J. Chem. Phys.
93
,
861
(
1990
).
9.
B.
Heumann
,
R.
Duren
, and
R.
Schinke
,
Chem. Phys. Lett.
180
,
583
(
1991
).
10.
R. Schinke, Photodissociation Dynamics, Spectroscopy and Fragmentation of Small Polyatomic Molecules (Cambridge University Press, Cambridge, England, 1993).
11.
B.
Heumann
,
K.
Weide
,
R.
Düren
, and
R.
Schinke
,
J. Chem. Phys.
98
,
5508
(
1993
).
12.
B.
Heumann
and
R.
Schinke
,
J. Chem. Phys.
101
,
7488
(
1994
).
13.
(a)
G.-J.
Kroes
,
M. C.
van Hemert
,
G. D.
Billing
, and
D. L.
Neuhauser
,
Chem. Phys. Lett.
271
,
311
(
1997
);
(b) G.-J. Kroes, M. C. van Hemert, G. D. Billing, and D. Neuhauser, J. Chem. Phys. (to be published).
14.
M. D.
Person
,
K. Q.
Lao
,
B. J.
Eckholm
, and
L. J.
Butler
,
J. Chem. Phys.
91
,
812
(
1989
).
15.
P. W.
Browning
,
E.
Jensen
,
G. C. G.
Waschewsky
,
M. R.
Tate
,
L. J.
Butler
, and
J. P.
Hessler
,
J. Chem. Phys.
101
,
5652
(
1994
).
16.
L.
Schnieder
,
W.
Meier
,
K. H.
Welge
,
M. N. R.
Ashford
, and
C. M.
Western
,
J. Chem. Phys.
92
,
7027
(
1990
).
17.
D. R.
Yarkony
,
J. Chem. Phys.
104
,
2932
(
1996
).
18.
J.
von Neumann
and
E.
Wigner
,
Phys. Z.
30
,
467
(
1929
).
19.
H. C.
Longuet-Higgins
,
Proc. R. Soc. London, Ser A
344
,
147
(
1975
).
20.
T.
Carrington
,
Faraday Discuss. Chem. Soc.
53
,
27
(
1972
).
21.
C. A.
Mead
,
J. Chem. Phys.
72
,
3839
(
1980
).
22.
A.
Kuppermann
and
Y.-S. M.
Wu
,
Chem. Phys. Lett.
205
,
577
(
1993
).
23.
H. C.
Longuet-Higgins
,
Adv. Spectrosc.
2
,
429
(
1961
).
24.
C. A.
Mead
and
D. G.
Truhlar
,
J. Chem. Phys.
70
,
2284
(
1979
).
25.
M. V.
Berry
,
Proc. R. Soc. London Ser. A
392
,
45
(
1984
).
26.
C. A.
Mead
,
Rev. Mod. Phys.
64
,
51
(
1992
).
27.
D. R.
Yarkony
,
J. Phys. Chem. A
101
,
4263
(
1997
).
28.
D. R. Yarkony, in Modern Electronic Structure Theory, edited by D. R. Yarkony (World Scientific, Singapore, 1995), pp. 642–721.
29.
G. G.
Balint-Kurti
,
Faraday Discuss. Chem. Soc.
91
,
123
(
1991
).
30.
B. H. Lengsfield and D. R. Yarkony, in State-Selected and State to State Ion-Molecule Reaction Dynamics: Part 2 Theory, edited by M. Baer and C.-Y. Ng (Wiley, New York, 1992), Vol. 82, pp. 1–71.
31.
V. Sidis, in State-Selected and State-to-State Ion-Molecule Reaction Dynamics Part 2, Theory, edited by M. Baer and C.-Y. Ng (Wiley, New York, 1992), Vol. 82, pp. 73–134.
32.
F. T.
Smith
,
Phys. Rev.
179
,
111
(
1969
).
33.
M.
Baer
,
Chem. Phys. Lett.
35
,
112
(
1975
).
34.
C. A.
Mead
and
D. G.
Truhlar
,
J. Chem. Phys.
77
,
6090
(
1982
).
35.
T.
Pacher
,
C. A.
Mead
,
L. S.
Cederbaum
, and
H.
Köppel
,
J. Chem. Phys.
91
,
7057
(
1989
).
36.
N. Matsunaga and D. R. Yarkony, Mol. Phys. (to be published).
37.
D. R.
Yarkony
,
J. Chem. Phys.
105
,
10456
(
1996
).
38.
C. A.
Mead
,
J. Chem. Phys.
78
,
807
(
1983
).
39.
K.
Docken
and
J.
Hinze
,
J. Chem. Phys.
57
,
4928
(
1972
).
40.
J.
Hinze
,
J. Chem. Phys.
59
,
6424
(
1973
).
41.
H.-J.
Werner
and
W.
Meyer
,
J. Chem. Phys.
74
,
5794
(
1981
).
42.
B. H.
Lengsfield
,
J. Chem. Phys.
77
,
4073
(
1982
).
43.
I. Shavitt, “The Method of Configuration Interaction,” in Modern Theoretical Chemistry, edited by H. F. Schaefer (Plenum, New York, 1976), Vol. 3, p. 189.
44.
B. O.
Roos
,
P. R.
Taylor
, and
P. E. M.
Siegbahn
,
Chem. Phys.
48
,
157
(
1980
).
45.
B. O.
Roos
,
Int. J. Quantum Chem. Symp.
14
,
175
(
1980
).
46.
P.
Siegbahn
,
A.
Heiberg
,
B.
Roos
, and
B.
Levy
,
Phys. Scr.
21
,
323
(
1980
).
47.
H. J.
Silverstone
and
O.
Sinanoglu
,
J. Chem. Phys.
44
,
1899
(
1966
).
48.
T. H. Dunning and P. J. Hay “Gaussian Basis Sets for Molecular Calculations,” in Modern Theoretical Chemistry, edited by H. F. Schaefer (Plenum, New York, 1976), Vol. 3.
49.
D. R.
Yarkony
,
J. Chem. Phys.
100
,
3639
(
1994
).
50.
D. R.
Yarkony
,
J. Chem. Phys.
104
,
7866
(
1996
).
51.
M. R.
Manaa
and
D. R.
Yarkony
,
J. Am. Chem. Soc.
116
,
11444
(
1994
).
52.
C. A.
Mead
,
Chem. Phys.
49
,
23
(
1980
).
53.
D. R.
Yarkony
,
J. Phys. Chem.
100
,
18612
(
1996
).
54.
M.
Baer
and
R.
Englman
,
Mol. Phys.
75
,
293
(
1992
).
55.
S.
Xantheas
,
S. T.
Elbert
, and
K.
Ruedenberg
,
J. Chem. Phys.
93
,
7519
(
1990
).
56.
S. S.
Xantheas
,
G. J.
Atchity
,
S. T.
Elbert
, and
K.
Ruedenberg
,
J. Chem. Phys.
94
,
8054
(
1991
).
57.
H.
Hettema
and
D. R.
Yarkony
,
J. Chem. Phys.
100
,
8991
(
1994
).
58.
K. P. Huber and G. Herzberg, Molecular Spectra and Molecular Structure IV. Constants of Diatomic Molecules (Van Nostrand Reinhold, New York, 1979).
59.
G. Chaban, M. S. Gordon, and D. R. Yarkony, J. Phys. Chem. (to be published).
60.
G. J.
Atchity
,
K.
Ruedenberg
, and
A.
Nanayakkara
,
Theor. Chem. Accounts
96
,
195
(
1997
).
61.
D. R. Yarkony, Theor. Chem. Accounts (to be published).
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