G-bands in the of Raman spectra of SWCNTs when interacting with electron donating and accepting molecules: (1) tetrathiafulvalene, (2) aniline, (3) pristine SWCNT, (4) nitrobenzene, (5) tetracyanoquinodimethane, and (6) tetracyanoethylene. Reproduced with permission from Ref. 59. Copyright 2008, American Chemical Society.