Acetylene bridged porphyrin–monophthalocyaninato ytterbium(iii) hybrids with strong two-photon absorption and high singlet oxygen quantum yield

Abstract

Several acetylene bridged porphyrin-monophthalocyaninato ytterbium(III) hybrids, PZn-PcYb, PH(2)-PcYb and PPd-PcYb, have been prepared and characterized by (1)H and (31)P NMR, mass spectrometry, and UV-vis spectroscopy. Their photophysical and photochemical properties, especially the relative singlet oxygen ((1)O(2)) quantum yields and the two-photon absorption cross-section (σ(2)), were investigated. These three newly synthesized compounds exhibited very large σ(2) values and substantial (1)O(2) quantum yields upon photo-excitation, making them potential candidates as one- and two-photon photodynamic therapeutic agents.

Diffraction can mimic saturation in multiphoton absorbers

“…Eq. (12). It should be noted that we performed the calculations with and without SE and obtained the same result in both cases.…”

“…Eqs. (12) and (13), cannot investigate the actual laser pulse shape as it propagates through the medium, which is a disadvantage for understanding the physics involved. Using Eq.…”

“…Applications in optical data storage and microfabrication are also promising [9][10][11] . In addition to many 2PA chromophores 12 , 3PA is frequently observed in organics and semiconductor quantum dots. [13][14][15][16] Some of the most appealing applications are found in the life sciences.…”

Lanthanide–tetrapyrrole complexes: synthesis, redox chemistry, photophysical properties, and photonic applications

“…The two-photon absorption cross section s 2 is large for these systems: 2347, 3301, and 2365 GM, respectively. 108 Boron dipyrromethene (BODIPY) is known for its light-harvesting and electron-acceptor properties. It has therefore been linked to phthalocyanine using phenyl-ethynyl bridges to form [Yb(Subst-Pc)CoP Me ] with Pc bearing different substituents: 2 BODIPY and 2 C 6 F 5 (Fig.…”

“…The underlying reasons for such bridging are to (i) enlarge the two-photon absorption cross-sections (s 2 ) of the complexes by increasing the intramolecular charge-transfer and coherent structure domain and (ii) enhance the simultaneous 1 O 2 production with two conjugated photosensitizing moieties. 108 The authors highlighted that the absorption spectra of the hybrids are not a superposition of the individual spectra of the porphyrin and the Yb III -phthalocyanine components. Singlet oxygen is efficiently produced in toluene upon one-or two-photon excitation either in the porphyrin Soret band or in the Q-band of the phthalocyanine: F D = 1.07-1.38, l ex = 416 nm; F D = 0.73-0.79, l ex = 675 nm.…”