Table 1.

Photophysical parameters of the compounds.^[a]

Compounds	λ abs [b]	ϵ [c]	λ em [d]	τ F [e]	Φ F [f]	τ T [g]	Φ Δ [h]	Φ T [i]
helical‐BDP	630	17.6	649	3.3	21 %	492	36 %	52 %
BDP	500	8.4	512	4.1	52 %	–[j]	–[j]	–[j]

[a] In dichloromethane (DCM), 25 °C. [b] Maximum absorption wavelength, in nm. [c] Molar absorption coefficient, 10⁴  m ⁻¹ cm⁻¹. [d] Maximum fluorescence emission wavelength, in nm. [e] Luminescence lifetimes, in nanoseconds (ns). [f] Fluorescence quantum yield with methyl blue as standard (Φ _F=3 % in MeOH). [g] Intrinsic triplet excited state lifetime, in microseconds (μs), c=3.1×10⁻⁷  m, low concentration was used to reduce the self‐quenching effect. [h] Singlet oxygen quantum yield with methyl blue as standard (Φ _Δ=57 % in DCM). [i] Triplet quantum yield determined by ns‐TA spectroscopy, by triplet‐triplet energy transfer method, with Methyl Blue as standard (Φ _T=50 % in MeOH). [j] Not observed.