Table 1 Photophysical properties of Alq3 and its derivatives
Compound
l
abs/nm (log e/MÀ1 cmÀ1
)
lema/nm
F Soln.b/solidc
E1/2red d/V
HOMOe/eV
LUMO/eV
Alq3
Al(1)3
Al(2)3
260 (5.15), 393 (3.93)
266 (5.17), 370 (5.05), 427 (4.73)
270 (4.99), 337 (4.78), 373 (4.75), 430 (4.44)
507
533
570
0.12/0.14
0.10/0.06
0.01/0.02
À2.40
À2.11
À2.22
À5.24
À5.21
À5.13
À2.40
À2.68
À2.60
In CH2Cl2 at 1 Â 10À5 M. Relative to Alq3 = 0.12.13 c Measured using an integration sphere. Measured in DMF relative to FeCp2
.
a
b
d
0/+
e
Determined from the reduction potential and the optical energy gap.
the presence of highly efficient thermal relaxation pathways.
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Al(1)3 and Al(2)3 are stronger electron acceptors than Alq3,
making these complexes promising for use as electron-
transport materials in OLEDs. In addition, both complexes
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