Characterization and Digital Restauration of XIV-XV Centuries Written Parchments by Means of Nondestructive Techniques: Three Case Studies

Table 2

Assignment of the main ATR-FTIR bands of the three parchments.

Wavenumber (cm^−1)			Band assignments
Parch. 34	Parch. 37	Parch. 38
3523; 3394			Gypsum (νOH)
3294	3291	3291	Collagen (Amide A) [4]
3087	3076	3078	Collagen (Amide B) [4]
2932; 2854	2919; 2854	2924; 2854	Collagen (νC–H) [4]
1796			ν1 + ν4 combination band of CO3^= [31]
1631	1631	1642	Collagen (Amide I) [overlapping with δH–O–H (approx. 1610) of structural H2O] [4]
1541	1548	1545	Collagen (Amide II)
1440	1430	1430	δCH2 [4]
1415	1413	1413	δipC–O–H (carboxylic side chains), δNH2 [4], ν3 asymmetric of CO3^= [3, 31]
1333	1337	1323	ωCH2/δC–H (methine) [4]
1236	1240	1242	Amide III [3]
	1200	1200	νC–O–C and δC–H [3]
	1162	1162	NH3 + residual modes [30]
1140 (sh)			ν3 calcium sulphate [4]
1113			Gypsum (ν3 SO4^=) [4]
1080 (sh)	1081	1081	νC–O or skeletal ν [30]
1034	1034	1034	νC–N [30]or νC–O–C and νC–O [3]
874	874	874	ν2 asymmetric of CO3^= [3, 25]
711 (sh)			ν4 symmetric of CO3^=
670		662	Gypsum (δantis SO4^=)
602		602	Gypsum (ν4as SO4^=) [4]

ν = stretching; δ = bending; d = deformation; ip = in-plane; sh = shoulder.