t parameter is made smaller
for hoover/drag style, the drag force accumulates over time so some
  oscillation in temperature can occur, for example
  &quot;rescale 300.0 300.0 1 0.0 0.0001&quot; will force (or keep)
  the temperature to be 300.0, the time frame over which the oscillations
  occur will become longer as the last parameter is made smaller
style springforce is designed to be applied to an entire group of atoms
  en masse (e.g. an umbrella force on an entire molecule)
for springforce style, the 