Modeling of amorphous polyaniline emeraldine base
Rights accessRestricted access - publisher's policy
Amorphous polyaniline emeraldine base has been investigated using atomistic classical molecular dynamics simulations. Initially, different sets of force-field parameters, which differ in the atomic charges and/or the van der Waals parameters, were tested. The experimental density of polyaniline was satisfactorily reproduced using the following combination: (i) equilibrium bond lengths, equilibrium bond angles, and electrostatic charges derived from quantum mechanical calculations and (ii) van der Waals parameters extrapolated from GROMOS for all atoms with the exception of the CH pseudoparticles of the phenyl ring, which were taken from an anisotropic united atom potential. Next, this force field was used to investigate the structure of the polymer in the amorphous state, the trajectories performed for this purpose allowing accumulation of 750 ns. Analyses of the energies evidence that the interactions between one repeating unit containing an amine nitrogen atom and another unit with an imine nitrogen are favored with respect to those between two identical repeating units. This conclusion is also supported by quantum mechanical and quantum mechanical/molecular mechanics calculations. On the other hand, the partial radial distribution functions indicate that this material only exhibits short-range intramolecular correlation, which is in excellent agreement with experimental evidence.
CitationCanales, M.; Curcó, D.; Alemán, C. Modeling of amorphous polyaniline emeraldine base. "Journal of physical chemistry B", 05 Agost 2010, vol. 114, núm. 30, p. 9771-9777.
- SIMCON - Grup de Recerca de Simulació per Ordinador en Matèria Condensada - Articles de revista 
- IMEM - Innovació, Modelització i Enginyeria en (BIO) Materials - Articles de revista 
- Departament d'Enginyeria Química - Articles de revista 
- Departament de Física i Enginyeria Nuclear - Articles de revista