Hydrogen bonds 6 Many-body potentials 6 Molecular dynamics 6 Absorption spectroscopy 4 Collective dynamics 4 Connectivity pattern 4 Dangling bonds 4 Instantaneous normal modes 4 Intermolecular distance 4 Isomers 4 Light absorption 4 Nuclear quantum effects 4 Polarization fluctuations 4 Quantum electronics 4 Spatial delocalization 4 ALLOTROPIC TRANSFORMATION 2 Atoms 2 COMPUTER SIMULATION 2 Computer simulation 2 Copper alloys 2 Disordered phases 2 Free energy 2 Free-energy difference 2 Isotopes 2 Isotopic fractionations 2 Kinetic energy 2 Low temperatures 2 MANY BODY POTENTIAL 2 Many body potential 2 Measured results 2