@article{3cb7ace421904439b3cc66d3a5d9686a,
title = "Electron spin echo envelope modulation spectroscopy (ESEEM) of the radical cations of 14N and 15N bacteriochlorophyll a",
abstract = "An electron spin echo envelope modulation frequency analysis is performed of the 14N and 15N bacteriochlorophyll a+ cation in solid solution. Hyperfine couplings of 2.0 and 3.1 MHz are derived which correspond to the perpendicular component of the axial hyperfine coupling tensor. Seven quadrupole frequencies were measured, six of which group in two sets of three zero-field quadrupole splittings.",
author = "Hoff, {A. J.} and {de Groot}, A. and Dikanov, {S. A.} and Astashkin, {A. V.} and Tsvetkov, {Yu D.}",
note = "Funding Information: P-860*, it has become clear that m this particular case with anisotropic hf cou~~ngs of the same order of magnitude as the isotropic values, ESEEM of r%ndom-Iy oriented samples does not yieId frequencies reflecting the isotropic couplings, but rather values much closer to the perpendicular component of the axral hf tensor. It appears that these values are much less use-fti for the assessment of the dimeric nature of P-860 than the isotropic hf couplings. ESE work on the singh crystals of bacterial reaction centers that have recently become availabIe [24-261 will remove the above srg-nalled difficulties and will hopefully allow a more precise detestation of the “N hf tensors and 14N quadrupole tensors [27] than has been possibie with ENDOR. Similar questions as discussed above on the delocalization of the unpaired electron of P-860+ can be raised for the triplet state of P-860. In this case conventional cw ENDOR experiments are dJ.fficult due to the short lifetime of 3P-860, whereas laser flash ESEEM offers good sensitivity. This will be demonstrated in the companion paper, where ESEEM experiments on 3P-860 and 3BChl a are presented [28] _ We are indebted to Dr. R. de Beer for his help in the transformation of some of the modulation traces, to Ms. Lenneke Nan and Mr. Frans Zonneveld for the preparation of the reaction centers and the BCld a, and to Dr. W. Lubik for co~u~cat~g to us his ENDOR results prior to publication. AJH is grateful to the Academy of Sciences, USSR, for supporting his sojourn in the Institute of Chemical Kinetrcs and Combustion, Novosibirsk. Part of this work was supported by the Netherlands Foundation for Chemical Research (SON), fin anced by the Netberiands Organization for the Advancement of Pure Research (ZWO).",
year = "1985",
month = jul,
day = "12",
doi = "10.1016/0009-2614(85)85263-5",
language = "English (US)",
volume = "118",
pages = "40--47",
journal = "Chemical Physics Letters",
issn = "0009-2614",
publisher = "Elsevier",
number = "1",
}