NEW STUDIES OF LIQUID AND SOLID-SURFACES USING 2ND HARMONIC-GENERATION

Optical second harmonic generation can probe the surfaces of diverse solid and liquid substrates. This technique is used to show that some amphiphilic monolayers spread on water change their surface orientation upon addition of specific solute molecules to the aqueous subphase. Second harmonic generation is also measured from thin mica crystals using a procedure which avoids complications from birefringence and interference effects. The resultant harmonic generation, which is asymmetric with respect to the mica surface, can be correlated with the crystallographic axes. © 1990.