sentences:  Graphene nanoribbons can be analyzed by scanning tunneling microscope, Raman spectroscopy, and infrared spectroscopy.For example, out-of-plane bending vibration of one C-H on one benzen ring, called SOLO, which is similar to zigzag edge, on zigzag GNRs has been reported to appear at 899 cm-1, whereas that of two C-H on one benzene ring, called DUO, which is similar to armchair edge, on armchair GNRs has been reported to appear at 814 cm-1 as results of calculated IR spectra.However, analyses of graphene nanoribbon on substrates are difficult using infrared spectroscopy even with a Reflection Absorption Spectrometry method.