Geopolymers Based on Phosphoric Acid and Illito-Kaolinitic Clay

Table 3

The principal IR bands and their corresponding species of raw and calcined clay.

Medenine clay		Calcined Medenine clay
Wavenumber (cm^−1)	Corresponding species	Wavenumber (cm^−1)	Corresponding species
3656, 3698	Hydroxyl groups (OH) of kaolinite	—	—
3624	Hydroxyl groups OH of illite	3624	Al-OH of illite
3434	OH of water	—	—
1648	H-O-H of water	—	—
1000, 1036, 1005	Si-O	1034	Si-O
470	Si-O	480	Si-O
789, 778	Doublet of quartz	789, 778	Doublet of quartz
536, 754	-OSi, -OSi of illite and kaolinite	—	—
694	Si-O-Si of quartz	694	Si-O-Si of quartz
912	Al-OH of kaolinite	—	—