H. Bottger et G. Kasner, VIBRATIONAL DENSITY-OF-STATES, DYNAMICAL STRUCTURE FACTOR AND EIGENSTATES OF ICOSAHEDRAL MODELS, Physica. B, Condensed matter, 220, 1996, pp. 339-341
Extending our previous studies on icosahedral models, we numerically c
alculate the integrated density of states (IDOS), the dynamical struct
ure factor, and special eigenstates of the ABCK tiling decorated by Da
nzer and Talis. We find a broadening of the structure factor at freque
ncies where the IDOS exhibits kinks. These kinks arise from a strong i
ncrease of the imaginary part of the Green's function (strong damping
of plane-wave modes) and indicate localization. The centers of the loc
alized vibrations mainly form icosahedra. The occurrence of distinct r
egimes in the IDOS may be related to the hierarchical structure of the
tiling. The flatness of the optical branches in the dynamical structu
re factor implies strong localization of optical modes.