A NOVEL-APPROACH TO ANALYZE THE OPTICAL 2ND-HARMONIC GENERATION ANISOTROPY AT SURFACES EMPLOYING INTERFERENCE TECHNIQUES - EXAMPLE - THE AU(110) ELECTRODE

Different sets of susceptibility coefficients a, b, c and d can reprod uce the same second harmonic generation (SHG) anisotropy curve, but on ly one set corresponds to the electronic and geometric structure of th e sample surface. A new approach, interference SHG anisotropy, is pres ented which is generally suitable to determine this physically relevan t set of coefficients. It is applied to the study of the SHG anisotrop y of the Au(110) electrode, which could not be analyzed hitherto. The distinct SHG response upon Br- adsorption indicates corresponding chan ges of the structural and electronic state of this interface. (C) 1998 Elsevier Science B.V.