Structure Determination of the Formate Intermediate on Cu(110) by Use of X-Ray-Absorption Fine-Structure Measurements

Abstract

A unique assignment of both the orientation and the adsorption site of formate (HCOO) on Cu(110) has been made by analysis of near-edge and extended x-ray-absorption fine structure. The species lies with its molecular plane perpendicular to the surface, aligned along the [$1\overline{1}0$] directions, and on top of the copper atoms of the outermost layer; the oxygen atoms almost bridge two copper atoms with an average Cu-O bond length of 1.98\ifmmode\pm\else\textpm\fi{}0.07 \AA{}, essentially identical to that in bulk copper formate.