Electronic and molecular structures of trigonal truxene-core systems conjugated to peripheral fluorene branches. Spectroscopic and theoretical study

Maria Moreno Oliva, Juan Casado, Juan T. Lopez Navarrete, Rory Berridge, Peter Skabara, Alexander L. Kanibolotsky, Igor F. Perepichka

Research output: Contribution to journalArticlepeer-review

35 Citations (Scopus)


An analysis is performed on the molecular and electronic features in a series of trigonal molecules constituted by a central truxene core which is ramified with three oligofluorene moieties of different lengths. Arms and core are studied independently and upon threefold unification. Special emphasis is paid to the modulation of the conjugational properties in relation to substitution, molecular dimension, ring aromaticity, intermolecular forces, oxidation state, etc. Raman and optical absorption/emission spectroscopies in conjunction with computational theoretical results are combined for this purpose. The evolution of some key intensity ratios in the Raman spectra (i.e., I1300/I1235) is followed as an indication of electronic interaction between the core and the branches. The changes of the electronic delocalization upon solvation, with varying temperature in the solid state, with the nature of the aromatic unit (bithiophene/fluorene) or after electrochemical oxidation are interpreted. The modulation of the optical properties on the basis of the structure and energetics of the orbital around the gap is also addressed. Density functional theory was used to assign the vibrational and electronic spectra.
Original languageUndefined/Unknown
Pages (from-to)4026-4035
Number of pages10
JournalJournal of Physical Chemistry B
Issue number16
Publication statusPublished - 26 Apr 2007


  • trigonal truxene-core systems
  • spectroscopy
  • peripheral fluorene branches

Cite this