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Site Directed Spin Labeling and EPR Spectroscopic Studies of Pentameric Ligand-Gated Ion Channels
Published on: July 4, 2016
Ferro- and antiferromagnetic exchange coupling constants in PELDOR spectra
D Margraf1, P Cekan, T F Prisner
1Institute for Physical and Theoretical Chemistry, Goethe-University, Max-von-Laue-Str.7, 60438 Frankfurt, Germany.
Abstract:
Pulsed electron electron double resonance (PELDOR) is a well-established method for measuring nanometer distances between paramagnetic centres. Here, we demonstrate on three rigid and conjugated biradicals how the presence of an exchange coupling constant J and its distribtion DeltaJ influences PELDOR data and its analysis. In principle two combinations of J and D fulfill the experimental data in each case. The correct one, including the sign of J, can be determined via simulations in case the two halves of the Pake pattern are separated enough.
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