Library Catalogue

Library Catalogue

  • external user (warningwarning)
  • Log in as
  • About the Catalogue

    Union Catalogue of Agricultural Libraries in the Netherlands

    The WUR Library Catalogue contains bibliographic data on books and periodicals held by the libraries of Wageningen University and Research Centre and some 15 associated libraries. Holding data are added to each record.

    Subjects covered include Agrotechnology, Food and Food Production, Plant and Animal Sciences, Soil Science, Geo-information, Landscape and Spatial Planning, Water and Climate, Ecosystem Studies, Economics and Society.

    The joint collections of the participating libraries cover a substantial part of the internationally available scientific literature in these disciplines.

    As far as Dutch scientific literature in these fields is concerned, coverage can be considered near 100%, including much of the so-called "grey literature".

    All titles are entered in their original language. Keywords are added to facilitate subject searching.

    The database is updated every day and now contains over 830.000 records.

Record number 104319
Title The molecular photophysics of chlorophyll : a study of its triplet state
show extra info.
[door] J.F. Kleibeuker
Author(s) Kleibeuker, J.F.
Publisher Wageningen : [s.n.]
Publication year 1977
Description 136 p.
Notes Proefschrift Wageningen
Tutors Schaafsma, Prof. Dr. T.J.
Graduation date 1977-06-03
Dissertation no. 689
Author abstract show abstract
The lowest excited triplet state T 0 of chlorophyll a , chlorophyll b , bacteriochlorophyll and corresponding pheophytins has been studied by magnetic resonance and optical spectroscopy. Zero field splitting (US) parameters D and E, populating rates, and depopulating rate constants for the three triplet spin states of these pigments have been obtained. The magnitude of the triplet state parameters for the various pigments has been correlated with the differences in molecular structure, especially with the extent and shape of the π-electron cloud. In particular it has been shown that effects of molecular structure on the ZFS parameter D and on the energy of T 0 can be accounted for by Gouterman's 4-orbital model when configuration interaction (CI) in T 0 and the lowest excited singlet state S 1 is of comparable magnitude. Furthermore it has been found that the effect of substitution of the central Mg 2+- ion by two protons is essentially different from the effects of changes in the structure of the outer porphyrin ring.

The considerable increase of the mean triplet decay constant on substitution of Mg 2+by 2H +cannot be accounted for by the energy-gap law. The presence of occupied non-bonding orbitals, as well as of N-H groups inducing additional promoting vibrational modes, are assumed to be responsible for the large increase of the non-radiative decay rate. There is experimental evidence that both effects are important.

The relatively stable and highly symmetric compound Mg-tetrabenzoporphin (MgTBP) has been found to be a good model compound for chlorophylls w.r.t. the effects of ligation on the lowest excited singlet states, but not for the triplet state T 0 . Some special properties of MgTBP are reported and discussed, i.e. the S 2 -fluorescence and the splitting of the lowest excited states S 1 and T 0 by Jahn-Teller coupling.

Online full textINTERNET
On paper FORUM ; STACKS ; NN08200,689
FORUM ; STACKS ; NN08202,689
Keyword(s) (cab) chlorophyll / energy / photosynthesis / vibration / molecules
Categories Photochemistry and Photophysics
Publication type PhD thesis
Language English
There are no comments yet. You can post the first one!
Post a comment

To support researchers to publish their research Open Access, deals have been negotiated with various publishers. Depending on the deal, a discount is provided for the author on the Article Processing Charges that need to be paid by the author to publish an article Open Access. A discount of 100% means that (after approval) the author does not have to pay Article Processing Charges.

For the approval of an Open Access deal for an article, the corresponding author of this article must be affiliated with Wageningen University & Research.

Please log in to use this service. Login as Wageningen University & Research user or guest user in upper right hand corner of this page.