Molecular Dynamics Simulations of Polycarbonate Doped with Lemke Chromophores

In the search for optimal electro-optical modulating materials we report in this work molecular dynamics
simulations of polycarbonate doped with Lemke chromophores which is a promising candidate system for
materials with such functionality. The simulations cover the electric field poling effects on the chromophore
order at a temperature above the glass transition temperature (Tg) of the material, the cooling procedure from
liquid state to the glass state in the presence of the poling field, and the back relaxation of the system after
removal of the field. Our study shows that electric field poling results in a higher chromophore order and that
the order is also maintained during the cooling procedure with the poling field applied. In the liquid state, the
applied poling field has little effect on the structure of the material. However, after the cooling procedure, the
structure changes significantly because the polymer matrix tends to become closely packed. Our study thus
indicates that for the bulk material, the structure of the host matrix is very important in determining the
performance of the material.