SELF-LOCALIZED SINGLE-ANHARMONIC VIBRATIONAL-MODES IN 2-DIMENSIONAL LATTICES

Many stationary forms of self-localized modes exist in a simple square and hexagonal lattice. They consist of a certain number of an elementary self-localized anharmonic mode (SLAM). This has several shapes depending on the uniform power of the nearest-neighbour interaction. By comparing SLAMs of the same vibrational frequency a binding energy can be derived for each stationary aggregated SLAM. Also infinite chains and whole lattices of elementary SLAMs are obtained. They have to be distinguished from standing waves of single-anharmonic phonons.