Perdomo-Ortiz, AlejandroWidom, Julia R.Lott, Geoffrey A.Aspuru-Guzik, AlanMarcus, Andrew H.2017-07-132012Perdomo-Ortiz, Alejandro, Julia R. Widom, Geoffrey A. Lott, Alán Aspuru-Guzik, and Andrew H. Marcus. 2012. “Conformation and Electronic Population Transfer in Membrane-Supported Self-Assembled Porphyrin Dimers by 2D Fluorescence Spectroscopy.” The Journal of Physical Chemistry B 116 (35) (September 6): 10757–10770. doi:10.1021/jp305916x.1520-61061520-5207http://nrs.harvard.edu/urn-3:HUL.InstRepos:33439071Two-dimensional fluorescence spectroscopy (2D FS) is applied to determine the conformation and femtosecond electronic population transfer in a dimer of magnesium meso tetraphenylporphyrin. The dimers are prepared by self-assembly of the monomer within the amphiphilic regions of 1,2-distearoyl-sn-glycero-3-phosphocholine liposomes. A theoretical framework to describe 2D FS experiments is presented, and a direct comparison is made between the observables of this measurement and those of 2D electronic spectroscopy (2D ES). The sensitivity of the method to varying dimer conformation is explored. A global multivariable fitting analysis of linear and 2D FS data indicates that the dimer adopts a “bent T-shaped” conformation. Moreover, the manifold of singly excited excitons undergoes rapid electronic dephasing and downhill population transfer on the time scale of ∼95 fs. The open conformation of the dimer suggests that its self-assembly is favored by an increase in entropy of the local membrane environment.en-USJournal Article10.1021/jp305916x