1.1 Porphyrins - Friedrich-Alexander-Universität Erlangen-Nürnberg

6 Experimental Section
UV/Vis spectroscopy was performed on a Shimadzu UV-3102 PC UV/Vis/NIR Scanning
Spectrophotometer or a SPECORD® S 600 spectrophotometer (Analytik Jena AG).
Mass spectrometry (MS) was done on either a MIRCOMASS ZABSPEC spectrometer (FAB + mode,
3-nitro benzylic alcohol as matrix) or on a Shimadzu AXIMA Confidence spectrometer (MALDI-
TOF, linear mode).
Elemental Analysis (EA) was done on a CE INSTRUMENTS EA 1110 CHNS.
Calculations were performed by utilization of ACCELRYS MATERIALS STUDIO® 99 or SPARTAN® 130 on
the semiempirical PM3 or PM6 level. Methods providing results achieved in cooperation
with the groups of C. MARIAN (University of Düsseldorf) or of G. BRINGMANN (University of
Würzburg) are referred to as references in the text.
Ground state absorption spectroscopy was performed on a commercial Shimadzu UV-
2501PC spectrophotometer.
Steady-state fluorescence spectroscopy was conducted in 1 cm×1 cm quartz cells by
utilization of the combination of a cw-Xenon lamp (XBO 150) and a monochromator (Lot-
Oriel, bandwidth 10 nm) for excitation and a polychromator with a cooled CCD matrix as
detector system (Lot-Oriel, Instaspec IV).
Decay associated fluorescence spectroscopy (DAFS): Those spectra were acquired using the
time correlated single photon counting (TCSPC) technique in combination with scanning of
the detection wavelength in an experimental setup known to literature. 106 A pulsed,
frequency doubled, linear polarized radiation of a Nd:VO4 laser (Cougar, Time Bandwidth
Products, wavelength: 532 nm, pulse width: 12 ps, repetition rate: 60 MHz) was used directly
for excitation of the samples or to synchronously pump a dye laser (Model 599, Coherent)
tunable in the range of 610 to 670 nm. Fluorescence was detected under a "magic" angle
relative to excitation. Data were analyzed by a homemade program in applying a variable
projection algorithm 107b to the global fitting problem. The Nelder-Mead simplex
algorithm 107a was used for optimization of the nonlinear parameters, and the support plane
approach 107c to compute error estimates of the decay times. Model functions were sums of
up to three exponentials convoluted by the instrument response function (42 ps as
measured with Ludox) including a time shift. Decay times and time shift were linked through
all measurements of one scan sampled every 2.5 nm.
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