(a)
𝜈
9
and
𝜈
2
+
𝜈
1
2
(b)
𝜈
1
1
(c)
𝜈
6
+
𝜈
1
0
(d)
𝜈
7
+
𝜈
8
Figure 2:
Beer-Lambert’s law plots of C
2
H
4
bands that were measured in the 640–3260 cm
−1
region: (a) combined
𝜈
9
and
𝜈
2
+
𝜈
1
2
, (b)
𝜈
1
1
, (c)
𝜈
6
+
𝜈
1
0
, and (d)
𝜈
7
+
𝜈
8
.