2026-05-29T23:15:27Zhttps://riuma.uma.es/rest/oai/request

oai:riuma.uma.es:10630/110162026-02-03T12:29:50Zcom_10630_2254col_10630_37959

Investigation of the long effective conjugation length in defect-free insulated molecular wires Ruiz-Delgado, María del Carmen Capel-Ferrón, Cristina Hernández-Jolín, Víctor López-Navarrete, Juan Teodomiro Brambilla, Luigi Tommasini, Mateo Milani, A. Castiglioni, Chiara Sugiyasu, K. Química física Due to the “insulation” of the π-conjugated backbones, insulated molecular wires (IMWs) are expected to be applied to various optoelectronic applications and nanotechnology.[1] Recently, Kazunori et al have succeeded in the synthesis of a self-threading polythiophene with a polyrotaxane-like 3D architecture (PSTB, see Figure 1), for which an intrawire hole mobility of 0.9 cm2 V−1 s−1 has been measured.[2] Here, we aim to evaluate the extent of π-conjugation along polythiophene backbones sheathed within defect-free “insulating” layers. A comparison between the experimental Raman spectra of the self-threading oligomers (i.e. 2STB-5STB) and the corresponding PSTB polymer indicates that: (i) the ratio of relative intensities of the two most intense Raman bands (I1375/1445) increases with the elongation of the size chain but does not saturate up to the pentamer, and (ii) π-conjugation spreads over 17–18 thiophene units in the polymer. Whether the effective conjugation length of the polymer is better described by using the long oligomer extrapolation approach[3] or periodic DFT calculations of the polymer is discussed in detailed by exploiting the very recent potentialities of state-of-the-art quantum chemical simulations of vibrational properties for crystalline solids.[ 2016-02-17T10:29:21Z 2016-02-17T10:29:21Z 2016 2016-02-17 conference output http://hdl.handle.net/10630/11016 eng 7th European Symposium of Computing pi-conjugated Compounds Burdeos, Francia 11-02-2016 open access by-nc-nd