Calculating the helical twisting power of dopants in a liquid crystal by computer simulation.

The helical twisting power determines the pitch of the helical structure produced by introducing a given concentration of chiral dopant molecules to a nematic liquid crystal phase. By using novel, twisted, periodic boundary conditions, and measuring the relative chemical potentials of right-and left-handed dopants in a twisted nematic phase, we have succeeded in measuring this property by computer simulation of a simple molecular model, for the rst time. The technique should be generally applicable.