  Quantum Monte Carlo is an efficient technique for finding the ground-state
energy and related properties of small molecules. A major challenge remains in
accurate determination of a molecule's geometry, i.e. the optimal location of
its individual nuclei and the frequencies of their vibration. The aim of this
article is to describe a simple technique to accurately establish such
properties. This is achieved by varying the trial function to accommodate
changing geometry, thereby removing a source of rather unpleasant singularities
which arise when the trial function is fixed (the traditional approach).
