Table 2.

Photophysical and oxygen quenching properties of compounds G0–G3 in aqueous and ethanol–methanol solutions at 298 K

	H2O							C2H5OH–CH3OH 4: 1 (v/v)
Solvent	λmax(B)/nm	λmax(Q)/nm	λemiss/nm	τ0/μsa	ϕ 0 b	kq/mmHg–1 s–1 (k2/107 M–1 s–1)c	ηq (air)d	τ0/μs	kq/mmHg–1 s–1 (k2/109 M–1 s–1)	ηq (air)d
G0	441	630	815	100 ± 2	0.02 ± 0.005	2320 ± 5.2 (146.8 ± 0.33)	0.97	240 ± 3	2863 ± 11.6(181.2 ± 0.7)	0.99
G1	445	637	815	240 ± 3	0.05 ± 0.01	315 ± 0.85 (19.9 ± 0.05)	0.92	260 ± 3	1415 ± 5.9 (89.6 ± 0.4)	0.98
G2	447	637	815	289 ± 3	0.06 ± 0.01	125 ± 0.16 (7.9 ± 0.01)	0.85	360 ± 4	611 ± 1.3 (38.7 ± 0.08)	0.97
G3	447	637	812	321 ± 3	0.07 ± 0.01	71 ± 0.10 (4.5 ± 0.01)	0.78	410 ± 4	550 ± 1.5 (34.8 ± 0.09)	0.97

^aObtained as intensity-weighted averages of lifetimes, determined from double-exponential fits: τ_av = (I₁τ₁ + I₂τ₂)/(I₁ + I₂), where I₁ and I₂ are initial intensities of the decays with lifetimes τ₁ and τ₂, respectively

^bPhosphorescence quantum yield in the absence of oxygen measured relative to the fluorescence of tetraphenylporphyrin (H₂TPP) in benzene (ϕ_fl = 0.11).³⁸

^cSee ref. 8 for definition of k₂.

^dCalculated based on the average values of τ₀ and k_q (eqn (2)).