document: Within the range of temperatures chosen, alanine dipeptide exhibits very simple behaviour. This result is due to the relatively small number of physically relevant minima (seven were characterised using this force field and solvent model) and the larger potential energy spacing between the global minimum and higher energy minima. Indeed, cross-overs in the approximate global free energy minimum for this system (where the free energy of the second-lowest potential energy minimum becomes lower than that of the global potential energy minimum) in the harmonic approximation would occur at 1170K. In general, the harmonic prediction for the crossover temperature between two minima is(4)kBTxo=V1−V2ln((o2ν¯2κ)/(o1ν¯1κ)),from Eq. (3), which clearly illustrates the balance between potential energy and well entropy.
extractive_keyphrases: alanine dipeptide balance between potential energy and well entropy force field and solvent model larger potential energy spacing physically relevant minima range of temperatures chosen
abstractive_keyphrases: cross-overs in the approximate global free energy