Table 1.

Spectroscopic and photolytic characteristics of cage compounds

Cmpd	λabs	ɛ(λabs)	ɛ(365)	ɛ(400)	Qu1	ɛQu1(365)	Qf1	λem	δf(740)	δf(800)	δu(740)	δu(800)
1*	262	5,100	180		0.14	25	∼0
2	345	5,900*	4,900	1,050	0.006	29	∼0				†	†
3	346	6,100	5,200	1,300	0.005	26	∼0				0.03	0.01
4	325	11,600	4,100	1,000	0.025	103	0.20	474	3.85 ± 0.31	1.26 ± 0.04	1.07 ± 0.05	0.13 ± 0.01
5	370	16,000	15,900	5,000	0.01	302	0.37	474	9.68 ± 0.32	3.22 ± 0.09	1.07 ± 0.07	0.34 ± 0.02
6	370	15,000	14,800	5,000	0.037	548	0.22	474	4.24 ± 0.12	1.41 ± 0.05	1.99 ± 0.09	0.42 ± 0.01
7	397	15,900	9,700	15,700	0.065	630	0.16	498			0.96 ± 0.05	3.1 ± 0.2
8	369	19,550	19,200	7,560	0.019	364					0.89 ± 0.24	0.42 ± 0.11
9	368	17,470	17,300	5,400	0.019	329	0.38	474		2.2‡	0.95 ± 0.21	0.37 ±0.06

λ_abs, wavelength in nm of absorbance maximum, ɛ, extinction coefficient in M⁻¹ cm⁻¹ at wavelength indicated; Q_u1, quantum efficiency for uncaging with one-photon excitation at 365 nm; Q_f1, quantum efficiency for fluorescence with one-photon excitation; λ_em, wavelength in nm for fluorescence emission peak; δ_f, fluorescence action cross section in 10⁻⁵⁰ cm⁴ s/photon for two-photon excitation at wavelength indicated (δ_f = δ_aQ_f2, where δ_a is the absorbance cross section and Q_f2 is the quantum efficiency for fluorescence, both with two-photon excitation); δ_u, uncaging action cross section in GM (10⁻⁵⁰ cm⁴ s/photon) for two-photon excitation at wavelength indicated (δ_u = δ_aQ_u2, where Q_u2 is the quantum efficiency for uncaging with two-photon excitation). Measurements were made in KMops at 24–25°C. Error estimates are standard deviations. 

*Values taken from the literature (30, 31); For compound 1, the entries listed under ɛ(365) and ɛQ_u1(365) actually refer to 360 nm. 

^†δ_u could not be measured because breakdown was dominated by dark hydrolysis with a 19.8-h exponential time constant. 

^‡Value was measured at 780 nm on an independent apparatus.