THE VIBRATIONAL-MODES AROUND THE SOLITON LATTICE WITH NEXT NEIGHBOR HOPPING INTERACTIONS IN HIGHLY DOPED TRANS-(CH)(X)

Starting from the extended SSH model that includes an external Coulomb potential arising from interchain charged solitons and counterions, t he intrachain e-e interaction and the next neighbor hopping interactio ns, eight localized vibrational modes around the soliton lattice have been found for the doping levels from 3.33 at.% to 13.33 at.%. Among t hem three are infrared active and they can be used to interpret the th ree observed infrared absorption lines at 487, 1284 and 1362 cm(-1). F urthermore, the frequencies of localized modes are decreased and their localizations are weakened when the dopant concentrations increase.