Chemistry Reference
In-Depth Information
He I
100 K
35
31
27
23
19
15
11
9
7
5
1
Γ
-1
-3
-5
-7
-9
-11
-13
-15
2.0
1.5
1.0
0.5
0.0
-0.5
-1.0
Binding Energy (eV)
Figure 6.10. ARUPS spectra taken on a TTF-TCNQ thin film at
T
100 K and
with 21.2 eV photons along the directions bisecting both
a
- and
b
-directions (polar
angles
θ
e
are shown). A parabolic background has been subtracted to enhance the
features. Reprinted from
Surface Science
, Vol. 482-485, C. Rojas, J. Caro, M.
Grioni and J. Fraxedas,
Surface characterization of metallic molecular organic thin
films: tetrathiafulvalene tetracyanoquinodimetane
, 546-551, Copyright (2001),
with permission from Elsevier.
discrepancies. According to this comparison we must conclude that band theory is
not appropriate to predict the experimental band structure of TTF-TCNQ and, as a
consequence, new theoretical approaches should be explored.
One
approach
consists
of
considering
electronic
correlations
since
it
is
well
known
that
TTF-TCNQ
undergoes
instabilities
of
the
4
k
F
type
(see
