| Steady-state absorption spectroscopy | Complexation produced a bathochromic shift of valPDI₂ absorption and a low-energy tail below 550 nm; Cor⊂valPDI₂ additionally showed broadening and an increased 0-1/0-0 vibronic peak-area ratio |
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| Steady-state fluorescence spectroscopy | valPDI₂ fluorescence was quenched upon complexation |
| Femtosecond transient absorption spectroscopy, approximately 30 fs excitation at 525 nm, 480–1000 nm probe | Intense negative 500–650 nm feature from overlapping ground-state bleach and stimulated emission; broad positive 600–1000 nm band peaking near 690 nm; within the first picosecond, partial recovery at 540–590 nm, reshaping at 850–950 nm, an approximately 10 nm redshift of the 690 nm maximum, and shoulders near 800 and 950 nm; red–NIR features assigned to PDI•⁻ photoproduct absorption |
| Femtosecond transient absorption spectroscopy, radical-cation signals | Direct PAH•⁺ signatures not clearly resolved; no distinct 610 nm PDI•⁺ absorption observed |
Giovanni Bressan, Erico M. Braun, Denis Hartmann, Ismael A. Heisler, Timothy A. Barendt. “Ultrafast charge separation controlled by aromatic guests in a perylene dimer.” ChemRxiv (). https://doi.org/10.26434/chemrxiv.15007724/v1
Values presented only in steady-state and transient spectroscopic plots were not transcribed
| Femtosecond transient absorption spectroscopy, stimulated-emission quenching at 580 nm | Charge-separation time constant τCS = 48 ± 5 fs; exponential fit started at 0.04 ps |
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| Femtosecond transient absorption spectroscopy, PDI•⁻ photoproduct absorption decay at 705 nm | Charge-recombination time constant τCR = 1530 ± 30 ps for T ≥ 2 ps; PDI•⁻ features remained at T = 2 ns |
| Femtosecond transient absorption spectroscopy, stimulated-emission quenching at 580 nm | Charge-separation time constant τCS = 243 ± 8 fs; exponential fit started at 0.04 ps |
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| Femtosecond transient absorption spectroscopy, PDI•⁻ photoproduct absorption decay at 705 nm | Charge-recombination time constant τCR = 350 ± 20 ps for T ≥ 2 ps; beyond approximately 500 ps, the 700 nm peak blueshifted and the visible–NIR positive signal progressively flattened |
| Femtosecond transient absorption spectroscopy, stimulated-emission quenching at 580 nm | Charge-separation time constant τCS = 80 ± 11 fs; exponential fit started at 0.04 ps |
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| Femtosecond transient absorption spectroscopy, PDI•⁻ photoproduct absorption decay at 705 nm | Charge-recombination time constant τCR = 1400 ± 400 ps for T ≥ 2 ps; PDI•⁻ features remained at T = 2 ns |
| Steady-state fluorescence spectroscopy, excitation below 550 nm | Broad, redshifted emission with a lifetime of approximately 17 ns |
| Time-correlated single-photon counting, excitation 570 nm, detection 750 nm | Fitted fluorescence lifetime 14 ns |
| Femtosecond transient absorption spectroscopy, excited-state absorption at 705 nm | Single-exponential decay 3100 ± 100 ps |
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