Chemisorption geometry of formate on TiO₂(110) by photoelectron diffraction

We have combined photoelectron diffraction in both scanned-angle and scanned-energy modes with Hartree-Fock calculations to investigate the interface structure of HCOO- on TiO2(110). Formate anions bind through the oxygens to Ti cation rows along [001] with a 2 × periodicity and an O-C-O bond angle of 126 ± 4°. Each anion binds to two Ti cations with an adsorbate-substrate bond distance of 2.0 ± 0.1 Å.