[en] Highlights: • Characteristics of Raman intensity and frequency trends using various $(n\text{,}n)$. • Interpretations of VDOSs representing Raman modes in the $(n\text{,}n)$. • Decomposition of 3-vibrational modes into radial, longitudinal, and tangential modes. • Unknown mode frequencies as the edge mode results from the finite-sized $(n\text{,}n)$. Raman intensity changes and frequency patterns have been studied using the various armchair ($n\text{,}n$) to understand the variations of bond polarizability, in regard to changing diameters, lengths, and the number of atoms in the ($n\text{,}n$). The Raman intensity trends of the ($n\text{,}n$) are validated by those of C_n isomers. For frequency trends, similar frequency patterns and frequency inward shifts for the ($n\text{,}n$) are characterized. Also, VDOS trends of the ($n\text{,}n$) expressing Raman modes are interpreted. The decomposition of vibrational modes in the ($n\text{,}n$) into radial, longitudinal, and tangential mode is beneficially used to recognize the distinct characteristics of vibrational modes.