Porphin resonance forms

Substrate resonances may also be affected by complexation to diamagnetic complexes, where the complexes possess ligands having a diamagnetic anisotropy [38]. Such compounds, e.g. chlorophyll or Ru" porphin show such effects. Here too the mutual interactions of the complexes themselves should be taken into account [39]. The thallium porphyrins cannot further complex and the aggregates are assumed to be formed from an electrostatic interaction between the porphyrin rings. 

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