l a;ind ¼
1
3
T bcd a
A
ab H
B
cd À a
B
ab H
A
cd
þ
1
105
T bcdeu a
A
ab U
B
cdeu À a
B
ab U
A
cdeu
þ
1
45
T bcdeu E
A
a;bcd H
B
eu À E
B
a;bcd H
A
eu
À
1
3
T be T ucd a
A
ab H
A
cd a
B
eu À a
B
ab H
B
cd a
A
eu
ð3:2:22Þ
and
l a;disp ¼
5C 6
54a 2 T be T ucd B
A
ab;cd a
B
eu À B
B
ab;cd a
A
eu
Á
ð 3:2:23Þ
Fig. 3.12 Coordinate system of the C 2 H 4 –C 2 H 4 complex (Reprinted with permission from Ref.
[100]. Copyright 2011 Wiley Periodicals, Inc.)
Fig. 3.13 Selected configurations of the C 2 H 4 –C 2 H 4 complex (Reprinted with permission from
Ref. [100]. Copyright 2011 Wiley Periodicals, Inc.)
3.2 Dipole Moment of van der Waals Complexes
41