Table 1: Band assignments of sub-peak and variation range of positions and widths of solvent-soluble [32,33].

Band assignments of hydrogen bonds Band position(cm-1) Width(cm-1)
Free OH groups 3611 30
OH-π hydrogen bonds 3530 ± 10 50 ± 20
Self-associated n-mers (n > 3) 3400 100 ± 10
OH-ether O hydrogen bonds 3280 ± 35 70 ± 15
Tightly bound cyclic OH tetramers 3150 ± 50 60 ± 10
OH-N (acid/base structure) 3100-2800 -
COOH dimers 2640 -