Figure 4.

The mean spectrum of each core cluster (A–C) minus the grand mean (D) of all core spectra. Substantial differences in the spectra of the RMT, IDC, and IDC_m groups are obvious and particularly notable in the regions assigned to vibrations of the nucleotide bases (≈1750-1400 cm⁻¹), the PO₂ structure (e.g., ≈1240 cm⁻¹), and deoxyribose (≈1100-900 cm⁻¹). Dramatic differences in the spectra between the IDC and the IDC_m are especially notable (see text for details).