Surface Functional Groups in Soil Clays

The surface reactivity of the solid phases in soils derives from the chemical behavior of surface functional groups in soil clays. A surface functional group is a chemically reactive molecular unit hound into the structure of a 

It is evident from these definitional remarks that the surface cheniistfy of a soil is determined in large measure by the nature of its surface functional groups. For this reason it is useful to consider the principal kinds of surface functional groups commonly found in soil clays. 

Surface hydroxyl groups coordinated to pairs of AP cations appear on the plane perpendicular to the crystallographic c axis in gibbsite (Fig. 1.2). This basal plane makes up most of the surface of the mineral, but it appears that the hydroxyl groups bound to Lewis add sites on the edge plane perpendicular to the basal plane are more reactive.These Lewis acid sites comprise an Al cation coordinated to a single water molecule. 

KAOl INITF SURFACE HYDROXYLS OUTFR-SPHERE SURFACE COMPIFX  

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