Polymer Modeling Applications of Symbolic Computation
Statistical models are employed to describe (a) the geometry and (b) kinetics of local conformational backbone motions in glassy polymers. First, 13 the chemical shift anisotropy (CSA) tensor line shape of an aromatic C is modeled using a double-well potential with temperature-dependent flips and oscillations modulating the experimental principal components. MACSYMA is used to perform matrix multiplications and subsequent Boltzmann averages. Second, bond-defect diffusion models lead to Levy-stable laws for conformer orientational survival probability densities. MACSYMA assists in the analysis and resummation of series expansions of stable laws needed for data processing.
KeywordsGlassy Polymer Chemical Shift Anisotropy Thermal Average Defect Diffusion Chemical Shift Anisotropy Tensor
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