Comments on “New types of interactions between solitary waves in (2Â +Â 1)-dimensions”

Starting from a special Bäcklund transformation, Bai and Zhao [Bai CL, Zhao H. Chaos, Solitons & Fractals. doi: 10.1016/j.chaos.2006.02.005] have claimed that a general variable separation solution of the (2 + 1)-dimensional nonlinear Schrödinger equation is derived. Based on the quite universal variable separation solution which is valid for some (2 + 1)-dimensional physical models and by selecting appropriate functions, they have asserted that new types of interactions between the multi-valued solitary waves and the single-valued solitary waves, i.e., the fractal semifolded localized structures, are investigated. We show that several serious wrongs exist in their paper, and say nothing of the conclusion that some new fractal semifolded localized structures for the (2 + 1)-dimensional nonlinear Schrödinger equation have been found.