Thermochromic distortions in a poly(3-alkylthiophene): an atomistic simulation investigation

The distortions in the backbone of poly(3-butylthiophene) that occur during the thermochromic change have been investigated by atomistic simulation of the polymer lattice. In the proposed model, one of the two chains in the u nit cell is displaced by half a repeat unit, thereby changing the stacking of the thiophene rings from a 'staggered' to an 'eclipsed' form, which favo urs the important out-of-plane deformations. (C) 2000 Elsevier Science S.A. All rights reserved.