Penta-co-ordinated aluminium in zeolites and aluminosilicates

Abstract

Solid state ²⁷Al n.m.r. spectroscopy of various aluminosilicates (zeolites, clays, amorphous SiO₂–Al₂O₃) shows that upon thermal or hydrothermal treatment a line appears at 30 p.p.m.; the position of this line suggests that penta-co-ordinated Al is present in all these aluminosilicates.