title: Charge transfer in porphyrin-calixarene complexes: ultrafast kinetics, cyclic voltammetry, and DFT calculations.
abstract: Transient absorption spectroscopy, cyclic voltammetry, and DFT calculations were used to describe charge transfer processes in a series of 5,10,15,20-tetrakis(N-methylpyridinium-n-yl) porphyrins (TMPyPn, n = 4,3,2) and TMPyPn/p-sulfonatocalix[m]arene (clxm, m = 4,6,8) complexes. Excitation of TMPyPn is accompanied by an increasing electron density at the methylpyridinium substituents in the order TMPyP2 < TMPyP3 < TMPyP4. The quenching of the excited singlet states of the complexes increases with the number of ionized phenolic groups of clxm and can be correlated with the partial transfer of the electron density from O(-) to the peripheral methylpyridinium substituents rather than to the porphyrin ring.
authors.affiliation: J. Heyrovský Institute of Physical Chemistry, v.v.i., Academy of Sciences of the Czech Republic, Dolejškova 3, 182 23 Praha 8, Czech Republic. kubat@jh-inst.cas.cz
authors.forename: Pavel
authors.initials: P
authors.lastname: Kubát
authors.forename: Jakub
authors.initials: J
authors.lastname: Šebera
authors.forename: Stanislav
authors.initials: S
authors.lastname: Záliš
authors.forename: Jan
authors.initials: J
authors.lastname: Langmaier
authors.forename: Marcel
authors.initials: M
authors.lastname: Fuciman
authors.forename: Tomáš
authors.initials: T
authors.lastname: Polívka
authors.forename: Kamil
authors.initials: K
authors.lastname: Lang
mesh_terms: D000042:Absorption; D047250:Calixarenes / Q000737:chemistry*; D004563:Electrochemistry; D004579:Electron Transport; D062385:Hydroxybenzoates / Q000737:chemistry; D007700:Kinetics; D008958:Models, Molecular; D008968:Molecular Conformation; D011166:Porphyrins / Q000737:chemistry*; D011789:Quantum Theory; D012996:Solutions
chemical_list: D062385:Hydroxybenzoates; D011166:Porphyrins; D012996:Solutions; C540459:meso-tetrakis(N-methylpyridinium-4-yl)porphyrin; D047250:Calixarenes; C017616:phenolic acid