Writing in a Polyaniline Film with Laser Beam and Stability of the Record: A Raman Spectroscopy Study

Table 1

Assignment of the Raman bands of PANI.

Band position (cm^−1)	Assignment	References
1640	Phenazine-like crosslinking	[22]
1620	C~C stretching vibrations of the phenylene ring	[24, 27–31]
1595	C~C stretching vibrations of the semiquinonoid ring	[27, 29, 32–36]
1563–1558	C=C stretching vibrations of the quinonoid ring	[27, 29, 32–36]
1504	N-H deformation in the semiquinonoid structures	[30, 33, 34, 37–39]
1480–1468	C=N stretching vibrations in quinonoid units	[25, 32]
1415	C–N stretching in highly localized polaronic structures	[27, 32, 40]
1377	C~N^+• stretching vibrations in highly localized polarons	[32]
1335	C~N^+• stretching vibrations of the semiquinone cation radicals in delocalized polaronic structures	[31, 37, 41]
1257	C–N stretching in quinonoid structures	[24, 31, 42]
1221	C–N stretching in benzenoid units	[24, 31, 42]
1194	C–H deformation vibration of a benzenoid ring	[32, 35, 36, 39, 43]
1182	C–H deformation vibration of a semiquinonoid ring	[32, 35, 36, 39, 43]
1164	C–H deformation vibration of a quinonoid ring	[32, 35, 36, 39, 43]
887	C~C ring deformation vibration (out-of-plane) of the polaronic form	[29]
834	C~C ring deformation vibration (out-of-plane) in the quinonoid ring	[32]
812	The benzene ring deformation in the emeraldine salt	[29]
780	Ring deformation in the emeraldine base	[27, 32]
751	Ring deformation in the emeraldine base	[27, 32]
608	Phenylene ring torsion	[22, 29, 32]
575	Phenazine-like crosslinking	[22]
533	Out-of-plane ring deformations in the emeraldine base	[21]
417	Out-of-plane ring deformations in the emeraldine base	[21, 29]