Structural formulas of porphycene (a) and porphyrin (b).
LIF excitation spectrum of porphycene in the range up to 1400 cm−1 excess energy above the origin of the S0-S1 electronic transition.
Active baseline subtraction spectrum (top, blue) of porphycene obtained while pumping the band of the LIF excitation spectrum. The scanning probe laser was delayed by 200 ns with respect to the fixed pump laser. (Bottom) The spectra obtained with and without pumping (black and red, respectively).
Comparison of LIF excitation (black, top) and dispersed fluorescence (red, bottom) spectra of porphycene in supersonic jet. Fluorescence intensity in the dispersed fluorescence spectrum is multiplied by −1 for easier comparison.
Dispersed fluorescence spectrum of porphycene recorded for excitation into the origin band (16 163 cm−1). Frequencies are given in wavenumbers relative to the excitation energy.
Comparison of dispersed fluorescence spectra obtained for selective excitation into both components of tunneling doublets: (a) and , (b) 107/112, (c) 136/141, (d) 150/155 cm−1.
Dispersed fluorescence spectra obtained for excitation into low-frequency bands: (a) 144 cm−1, (b) 174 cm−1, (c) 220 cm−1, (d) 398 cm−1.
Dispersed fluorescence spectrum obtained via excitation of (a) 0+ 184, (b) 0+362, (c) 0+364, and (d) 0 + 541 cm−1 bands.
Dispersed fluorescence spectrum obtained for excitation into (a) 0 + 339, (b) 0 + 364, (c) 0 + 400, (d) 0 + 481, and (e) 0 + 519 cm−1 bands.
Dispersed fluorescence spectra obtained via excitation of (a) 0 + 826 cm−1, (b) 0 + 909 cm−1, and (c) 0 + 951 cm−1 bands.
Comparison of experimental and calculated vibrational modes of porphycene in the ground (bottom) and the lowest excited singlet state (top). A and C, B3LYP/6-31G(d,p), B and D, B3LYP/6-311++G(d,p) calculations. The plots for S0 include also the 8Ag mode at 810 cm−1, 27 not observed in the present work.
Displacement vectors of 1Ag, 2Ag, 1Bg, and 2Bg normal modes, obtained using B3LYP/6-311++G(d,p) calculations.
Ground and excited state (S1) vibrational frequencies of porphycene obtained from LIF and SVL fluorescence spectra.
Comparison of experimental and calculated low frequency modes of porphycene in S0 and S1 electronic states. The calculated values include scaling factors (see text).
Ground state tunneling splitting of the 2Ag mode obtained from SVL spectra for different vibrationally excited levels.
Article metrics loading...
Full text loading...