# IR and Raman Dual Modality Markers Differentiate among Three _bis_-Phenols: BPA, BPS, and BPF
## 3 Results
### IR and Raman Band Assignment
One of the IR pairs (1497 cm\({}^{-1}\) and 1441 cm\({}^{-1}\)) is in the same spectral range as CH\({}_{3}\) in CH\({}_{3}\)-C-CH\({}_{3}\) deformation (1459 cm\({}^{-1}\)) except that the deformation in BPA is detected in the Raman spectrum and not in the IR spectrum. The full-range IR and Raman spectra of BPF (Figure 4) assigns vibrational modes characteristic of this bis-phenol structure containing a H2C-phenol moiety which is exactly the same moiety in the side chain of the amino acid tyrosine. The same wavenumbers assigned by [PERSON] et al. [18] to tyrosine include all the vibrational modes for H2C-phenol in BPF. The four highest intensity peaks in IR peaks (809 cm\({}^{-1}\), 1230 cm\({}^{-1}\), 511 cm\({}^{-1}\), and 1510 cm\({}^{-1}\)) are unique to IR except one (Raman 1508 cm\({}^{-1}\)). The four highest intensity peaks in Raman (3056 cm\({}^{-1}\), 845 cm\({}^{-1}\), 815 cm\({}^{-1}\), and 1608 cm\({}^{-1}\)) are predominantly unique to Raman except one (IR 1612 cm\({}^{-1}\)). The assignments of wavenumbers to vibrational modes are listed in Table 3. Assignments numbering specific ring carbons in the phenolic ring resulting in individually observed wavenumbers are also available in [PERSON] et al. [21]. The numbering in BPF is not reported because of the uncertainty of which set of specific sites in each phenolic ring can discerned as identical. \begin{table}
\begin{tabular}{c c c} \hline
**Wavenumber (cm\({}^{-1}\))** & **IR Assignments** & **Raman Assignments** \\ \hline
2973 & C-H str in CH\({}_{3}\) sym & \\
3066 & OH op str asym & \\ \hline ip = in-plane; op = out of plane; oop = out of plane on two adjacent sites; sym = symmetrical mode; asym = asymmetric mode. & \\ \end{tabular}
\end{table} 
Table 1: _Cont._ \begin{table}
\begin{tabular}{c c c} \hline \hline
**Wavenumber (cm\({}^{-1}\))** & **IR Assignments** & **Raman Assignments** \\ \hline
498 & & O-S-C bend asym \\
544 & O-S-O bend sym \\
550 & & O-S-O bend asym \\
628 & & C-C-C-O-H twist asym \\
646 & C-C-C-OH twist sym \\
688 & S-O stretch sym \\
721 & H-C-C-C twist \\
813 & C-C-C-H twist \\
823 & & C-C-C-H twist asym \\  
OH op stretch \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Vibrational mode assignments of BPS. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Wavenumber (cm\({}^{-1}\))** & **IR Assignments** & **Raman Assignments** \\ \hline
489 & & C-C-C oop bend \\
494 & & C-C-C oop bend \\
511 & C-C-O-H bend & \\
562 & & C-C-C ip bend \\
569 & C-C-C ip bend & \\
636 & & C-C-O torsion \\
670 & C-C-C bend + C-H wag & \\
776 & C-C-C bend + O-H wag & \\
809 & C-C-C trigonal bending asym & C-C-C bend + O-H wag \\
815 & **a** & \\
845 & **b** & \\
909 & Ring breathing & C-C-C trigonal bending asym \\
1013 & C-H oop bend) sym & C-C-C trigonal bending asym \\
1096 & & C-H-C-H scissoring sym \\
1100 & H-C-H scissoring sym & \\
1166 & & H-C-H scissoring asym \\
1169 & C-H oop bend sym & \\
1230 & O-H bend + CH\({}_{2}\) twist sym & C-H oop bend asym \\
1250 & & C-H in CH\({}_{2}\) bending \\
1382 & C-H in CH\({}_{2}\) bending & \\
1422 & & O-H bend + CH\({}_{2}\) twist asym \\
1450 & H-C-H scissoring sym & \\
1508 & & C-O-H bending asym \\
1510 & CH ip bend in phase sym & \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Vibrational mode assignments of BPF.