Overdamped solvent motion

A particular question of interest is whether the DNA torsional motions observed on the nanosecond time scale are overdamped, as predicted by simple Langevin theory, and as observed for Brownian motions on longer time scales, or instead are underdamped, so that damped oscillations appear in the observed correlation functions. A related question is whether the solvent water around the DNA exhibits a normal constant viscosity on the nanosecond time scale, or instead begins to exhibit viscoelastic behavior with a time-, or frequency-, dependent complex viscosity. In brief, are the predictions for... 

The kinetic energy is negligible in a viscous solvent where the motion is overdamped. Then, the Boltzmann distribution with Eq. 1.51 gives the probability (im-normalized) for a specific arrangement of Tq, ...,... 

Solvent viscosity makes the motion overdamped and therefore relaxadonal. Different modes of motion are observed over an extended range at the low frequencies. 

In a viscous solvent the motion of the particle is overdamped. Then, the equation of motion of the particle has the friction term and the force term only ... 

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