125471.fig.008a
(a)
125471.fig.008b
(b)
Figure 8: Polarized IR spectra of (a) d1-2-furanacetic acid and (b) d1-2-furanacrylic acidcrystals measured at room temperature in the 𝜈 O D band frequency range. (a) 2-furanacetic acid crystal (ca. 10% H and 90% D). (I) The electric field vector 𝐸 parallel to the 𝑎 -axis, (II) The 𝐸 vector parallel to the 𝑐 *-axis (b) 2-furanacrylic acid crystal (ca. 65% H and 35% D). (I) The electric field vector 𝐸 parallel to the 𝑐 -axis, (II) The E vector parallel to the 𝑎 *-axis.