Soliton pair charge storage in doped polyene molecules: Evidence from photoelectron spectroscopy studies

M. Lögdlund; P. Dannetun; S. Stafström; W. R. Salaneck; M. G. Ramsey; C. W. Spangler; C. Fredriksson; J. L. Brédas

doi:10.1103/PhysRevLett.70.970

Soliton pair charge storage in doped polyene molecules: Evidence from photoelectron spectroscopy studies

M. Lögdlund, P. Dannetun, S. Stafström, W. R. Salaneck, M. G. Ramsey, C. W. Spangler, C. Fredriksson, and J. L. Brédas

Phys. Rev. Lett. 70, 970 – Published 15 February 1993

Abstract

The π-electronic structural changes in a polyene molecule containing seven double bonds, α,ω-diphenyltetradecaheptaene (DP7), have been studied upon gradually doping with sodium, using x-ray and ultraviolet photoelectron spectroscopies. The spectra are interpreted with the help of detailed quantum chemical calculations. Analysis of the evolution of the XPS and UPS spectra as a function of doping with sodium indicates that the extra charges are stored in the form of two charged solitons on the polyene part of the molecules, which results in two new energy levels in the originally forbidden energy gap.