The G-factor anistropy of plant chlorophyll a{sup +}.
High-field EPR experiments at 12 T/330 GHz were performed on chlorophyll a radical cations in methylene chloride at low temperatures. Using fully deuterated chlorophyll it was possible to obtain the principal components of the rhombic g-tensor as g{sub {alpha}} = 2.00329 {+-} (5 x 10{sup -5}), g{sub {beta}} = 2.00275 {+-} (8 x 10{sup -5}), and g{sub {gamma}} = 2.00220 {+-} (8 x 10{sup -5}). Protonated chlorophyll radicals did not give enough spectral resolution to yield the g-anisotropy from the EPR spectrum. This was true even at higher field/frequency combinations up to 24 T/670 GHz. Semiempirical calculations were performed using the INDO/S method (ZINDO) which yielded good agreement with the experimental data.
- Research Organization:
- Argonne National Laboratory (ANL)
- Sponsoring Organization:
- SC; OUS; NSF; DOD
- DOE Contract Number:
- AC02-06CH11357
- OSTI ID:
- 942899
- Report Number(s):
- ANL/CHM/JA-35754
- Journal Information:
- J. Phys. Chem., Journal Name: J. Phys. Chem. Journal Issue: 30 ; Aug. 3, 2000 Vol. 104; ISSN 1089-5647; ISSN JPCBFK
- Country of Publication:
- United States
- Language:
- ENGLISH
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