Labile electronic ground state of the π-cation radical of zinc(II) tetraphenylporphyrin:: a variable-temperature ESR investigation

被引:0
作者
Dave, PC [1 ]
Srinivas, D [1 ]
机构
[1] Cent Salt & Marine Chem Res Inst, Sophisticated Analyt Instruments Lab, Bhavnagar 364002, Gujarat, India
关键词
porphyrin; EPR; pi-cation; zinc(II) tetraphenylporphyrin; electronic ground state;
D O I
10.1002/(SICI)1099-1409(199805/06)2:3<243::AID-JPP83>3.3.CO;2-B
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
The UV-vis and variable-temperature X-band EPR spectral studies (298-77 K) on pi-cation of zinc(II) tetraphenylporphyrin (ZnTPP) have revealed for the first time a labile electronic ground state. The electronic structure changes from (2)A(2u) to (2)A(1u) as the temperature is lowered from 298 to 150 g Axial ligands and sigma-donor solvents show a significant effect on the spectral data. The lability in the ground state electronic configuration is attributed to the flexibility of the porphyrin moiety in changing from a 'ruffled' to a lower symmetry. (C) 1998 John Wiley & Sons, Ltd.
引用
收藏
页码:243 / 248
页数:6
相关论文
共 37 条
[21]   HIGH-VALENT IRON-PORPHYRIN COMPLEXES RELATED TO PEROXIDASE AND CYTOCHROME-P-450 [J].
GROVES, JT ;
HAUSHALTER, RC ;
NAKAMURA, M ;
NEMO, TE ;
EVANS, BJ .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1981, 103 (10) :2884-2886
[22]   ON THE MECHANISM OF OLEFIN EPOXIDATION BY OXO-IRON PORPHYRINS - DIRECT OBSERVATION OF AN INTERMEDIATE [J].
GROVES, JT ;
WATANABE, Y .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1986, 108 (03) :507-508
[23]   ELECTRON PATHWAYS IN CATALASE AND PEROXIDASE ENZYMIC CATALYSIS - METAL AND MACROCYCLE OXIDATIONS OF IRON PORPHYRINS AND CHLORINS [J].
HANSON, LK ;
CHANG, CK ;
DAVIS, MS ;
FAJER, J .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1981, 103 (03) :663-670
[24]   THE ORIGIN OF INFRARED MARKER BANDS OF PORPHYRIN PI-CATION RADICALS - INFRARED ASSIGNMENTS FOR CATIONS OF COPPER(II) COMPLEXES OF OCTAETHYLPORPHINE AND TETRAPHENYLPORPHINE [J].
HU, SZ ;
SPIRO, TG .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1993, 115 (25) :12029-12034
[25]   ELECTRON-SPIN-RESONANCE SPECTRA OF 6-COORDINATE COBALT(III) TETRAPHENYLPORPHYRIN CATION RADICALS GENERATED BY ELECTROCHEMICAL OXIDATION .2. AXIAL LIGAND AND SOLVENT EFFECTS [J].
ICHIMORI, K ;
OHYANISHIGUCHI, H ;
HIROTA, N ;
YAMAMOTO, K .
BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 1985, 58 (02) :623-630
[26]   RUFFLING IN A SERIES OF NICKEL(II) MESO-TETRASUBSTITUTED PORPHYRINS AS A MODEL FOR THE CONSERVED RUFFLING OF THE HEME OF CYTOCHROMES-C [J].
JENTZEN, W ;
SIMPSON, MC ;
HOBBS, JD ;
SONG, X ;
EMA, T ;
NELSON, NY ;
MEDFORTH, CJ ;
SMITH, KM ;
VEYRAT, M ;
MAZZANTI, M ;
RAMASSEUL, R ;
MARCHON, JC ;
TAKEUCHI, T ;
GODDARD, WA ;
SHELNUTT, JA .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1995, 117 (45) :11085-11097
[27]   NUCLEAR MAGNETIC-RESONANCE STUDIES OF METALLOPORPHYRIN PI-CATION RADICALS AS MODELS FOR COMPOUND-I OF PEROXIDASES [J].
MORISHIMA, I ;
TAKAMUKI, Y ;
SHIRO, Y .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1984, 106 (25) :7666-7672
[28]  
NAPPA M, 1978, J AM CHEM SOC, V100, P5057
[29]  
Norris J.R., 1979, The Porphyrins, VIV, P159
[30]  
SATOH M, 1992, INORG CHEM, V31, P298