It has been proposed [1,2] and numerically demonstrated [3] that a large amplitude vibration in a perfect 1-D lattice can localize because of anharmonicity. More detailed analytical and numerical investigations of classical 1-D anharmonic chains made possible by simple eigenvalue generating recursion relations have revealed a variety of stable intrinsic localized modes with frequencies outside of the plane wave bands [3-8]. Recently quantum mechanical aspects of ILMs (Intrinsic Localized Modes) have been considered [9,10]. Some progress also has been reported for higher dimensional classical crystal lattices with simple nearest-neighbor model interactions [11,12]. Particularly important has been the recognition that diatomic crystal potentials like the Born-Mayer-Coulomb in 1-D produces an intrinsic gap mode (IGM)

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[12] S.Flach, K.Kladko, and C.R.Willis, Phys. Rev. E

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Last modified: April 3, 1997