Purpose

MetaPotential module to abstract hybrid schemes such as LOTF and the local energy scheme into a Potential like object to facilitate activities such as geometry optimisation.

From the outside, a MetaPotential looks rather like a standard QUIP Potential, with interfaces for Initialise, Finalise, Print, Cutoff and Calc.

It can also be used to geometry optimise an Atoms structure, using the Minim interface.

MetaPotential_LOTF also has to live in this module so that it can call MetaPotential_minim() without any circular depenendancies.