ELECTRON-SPIN POLARIZATION TRANSFER FROM EXCITED TRIPLET PORPHYRINS TO A NITROXIDE RADICAL VIA A SPIN-EXCHANGE MECHANISM

被引：55

作者：

FUJISAWA, JI ^{[1
]}

ISHII, K ^{[1
]}

OHBA, Y ^{[1
]}

IWAIZUMI, M ^{[1
]}

YAMAUCHI, S ^{[1
]}

机构：

[1] TOHOKU UNIV,INST CHEM REACT SCI,AOBA KU,SENDAI,MIYAGI 980,JAPAN

来源：

JOURNAL OF PHYSICAL CHEMISTRY | 1995年 / 99卷 / 47期

关键词：

D O I：

10.1021/j100047a006

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

CIDER mechanisms in systems of excited triplet tetraphenylporphyrins (MTPP; M = H-2, Mg, Zn, Cd) and TEMPO were studied by time-resolved EPR. It was found that dominant polarizations generated on TEMPO are net emissions for H2TPP and MgTPP and net absorptions for ZnTPP and CdTPP, which are the same as the polarizations of the corresponding triplet (T-1) porphyrins. The polarizations were diminished with a spin-lattice relaxation time of TEMPO. A polarized T-1 signal of ZnTPP was observed in paraffin solution and was quenched by TEMPO. These facts clearly indicate that these polarizations are due to an electron spin polarization transfer mechanism. This is the first definitive demonstration of ESPT in triplet-doublet systems.

引用

页码：17082 / 17084

页数：3

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