11574 J. Phys. Chem. A, Vol. 114, No. 43, 2010
Deniz et al.
and 532 nm (30 mJ) and the emission intensity was measured
at 580 nm with and without a long-pass filter (>490 nm) in
between laser and sample.
Acknowledgment. We thank the the NSF (CAREER Award
CHE-0237578 and CHE-0749840) and MIUR (PRIN 2008) for
financial support.
Supporting Information Available: Experimental proce-
dures for the syntheses of 3a, 4a, 5a, 22a, and 25 and their
precursors; steady-state absorption and emission spectra of 19a
and 22a; redox potentials of 20, 21, 29, and 30; steady-state
emission spectra of 23-25; absorbance evolution upon excita-
tion of 3a and 5a; determination of the quantum yield for the
photochromic transformations. This material is available free
References and Notes
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