RING LIKE TPPS4 J-AGGREGATE STRUCTURE

Self assembling nanostructures of Meso-tetra (4-sulfonatophenyl) porphine (TPPS4) were investigated using atomic force microscope (AFM) and scanning tunneling microscope (STM). It was shown that TPPS4 forms long up to 1 pm length 19 nm diameter nanotubes. Also short "standing" nanotubes (10 nm height) were observed. Investigations with STM showed that TPPS4 molecules forms 17,5 nm diameter ring like structures. These ring like structures are primary TPPS4 J-aggregate structures formed by stacking TPPS4 molecules by zigzag model. We propose a new TPPS4 nanotube formation model winding of linear threads to a 18 nm diameter spiral.