Table 5: Peaks present in the spectra after the HF treatment.
Peak position Vibration mode Carrier Possible interpretation

(cm^-1)

806-800 Si-O siloxane remaining silicone oil

$\sim$ 1000 Si-O stretching silicate remaining silicates

1095-1080 Si-O stretch siloxane remaining silicone oil

1260 Si-O stretching siloxane remaining silicone oil

1375 COO^- sym stretch organic carbox. acid salts

1460-1447 C-H bending/CO₃^- organic/carbonate ion aliphatic/remaining carbonates

1500-1450 C=C stretching organic aromatic rings

1585 COO^- antisym stretch organic carbox. acid salts

$\sim$ 1600 C=C ring stretch organic aromatic rings

1714-1700 C=O stretch organic ketone/carboxylic acid

3000-2800 CH₂; CH₃ sym and asym stretch organic aliphatic hydrocarbons

3600-2400 (centered at 3250) OH stretch organic alcohols, carbox. acids, phenols

**Table 5:** Peaks present in the spectra after the HF treatment.
Peak position	Vibration mode	Carrier	Possible interpretation
(cm^-1)
806-800	Si-O	siloxane	remaining silicone oil
$\sim$ 1000	Si-O stretching	silicate	remaining silicates
1095-1080	Si-O stretch	siloxane	remaining silicone oil
1260	Si-O stretching	siloxane	remaining silicone oil
1375	COO^- sym stretch	organic	carbox. acid salts
1460-1447	C-H bending/CO₃^-	organic/carbonate ion	aliphatic/remaining carbonates
1500-1450	C=C stretching	organic	aromatic rings
1585	COO^- antisym stretch	organic	carbox. acid salts
$\sim$ 1600	C=C ring stretch	organic	aromatic rings
1714-1700	C=O stretch	organic	ketone/carboxylic acid
3000-2800	CH₂; CH₃ sym and asym stretch	organic	aliphatic hydrocarbons
3600-2400 (centered at 3250)	OH stretch	organic	alcohols, carbox. acids, phenols

Source LaTeX | All tables | In the text

	1 Introduction
	2 Materials and methods
	3 Results
	4 Discussion
	5 Conclusions and perspectives
	References