Table 1 Details of the main peaks composing the resolved spectra obtained for each pure component using MCR-ALS and corresponding assignments^{17,19,36,37,38,39,58,59,60}.

Peak positions (cm−¹)

1466

C-H bending; N-H bending

^17,58,59

1473

X-OH bending (X = Si, Mg, Fe)

^36,37,38

1539

N-H bending; C = C stretching

^17,58,59

1541

1543

X-OH bending (X = Si, Mg, Fe)

^36,37,38

1576

X-OH bending (X = Si, Mg, Fe)

^36,37,38

1597

X-OH bending (X = Si, Mg, Fe)

^36,37,38

1628

interlayer H-O-H

^19,38,39

1641

X-OH bending (X = Si, Mg, Fe)

^36,37,38

1672

1670

X-OH bending (X = Si, Mg, Fe)

^36,37,38

1711

X-OH bending (X = Si, Mg, Fe)

^36,37,38

1730

aromatic C = O stretching

^17,58,59

1747

X-OH bending (X = Si, Mg, Fe)

^36,37,38

1776

Si-O secondary order overtone

⁶⁰

2852

C-H stretching

^17,58,59

2924

C-H stretching

^17,58,59

2958

C-H stretching

^17,58,59