Peterson with co-workers have observed FOs generated by point defects on Cu(111) surface with periodicity of approx. 17 Å at -2.4 mV. They further confirmed the find with power images of the FT-STM. Interestingly, using the same technique, they have also observed that the oscillatory pattern formed on the herringbone reconstructed Au(111) surface arises from two surface states (kF = 0.17 ± 0.02 Å -1 ) and bulk (kF = 0.21 ± 0.02 Å -1 ) electrons. Same has also appeared to hold for the Cu(111) with surface electron state kF = 0.21 Å -1 and bulk contribution kF = 0.24 Å -1 . As mentioned by the authors , both bulk electrons kF values agree with magnetoacoustic effect data. The theoretical description they have applied is similar to the above-discussed Crommie 24 approach.