measurements of such sharp CPL spectra require careful setting of bandwidth for the
quantitative evaluation of CPL intensity.
Figure 14.9a shows the change in the CPL spectrum of Eu(facam) 3 with fluorescence bandwidth. As the fluorescence bandwidth is increased, the CPL spectrum
becomes broader, and g lum in the vicinity of 595 nm decreases slightly. Therefore,
for compounds showing a very sharp CPL spectrum like Eu(facam) 3 , it is necessary
to use a small fluorescence bandwidth to perform high-resolution measurements.
Figure 14.9b shows a comparison of the fluorescence spectrum obtained using the
CPL-300 with a fluorescence bandwidth of 3 nm and that obtained using the generalpurpose FP-8300 fluorescence spectrophotometer with a fluorescence bandwidth of
2.5 nm. The good agreement between these spectra reveals that the CPL-300 is
capable of high-resolution measurements. Since a trade-off relation exists between
the bandwidth of the instrument and the signal-to-noise ratio (S/N), when measuring
faint CPL signals at high resolution, cumulative measurements should be performed.
-1
0.2
-300
300
0
0.25
CPL [mdeg]
g
lum
560
660
580
600
620
640
Wavelength [nm]
FL [Arb. Unit]
Eu(facam) 3
Fig. 14.8 CPL and fluorescence spectra of 5.5-mM Eu(facam) 3 in dimethyl sulfoxide (DMSO) at
room temperature
14 Principles and Applications of Circularly Polarized Luminescence. . .
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