DFT study of Pt adsorption on low index SrTiO 3 surfaces: SrTiO 3 (1 0 0), SrTiO 3 (1 1 1) and SrTiO 3 (110) Aravind Asthagiri a,b , David S. Sholl a, * a Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA b Geophysical Laboratory, Carnegie Institution of Washington, Washington, DC 20015, USA Received 15 September 2004; accepted for publication 18 February 2005 Available online 10 March 2005 Abstract Density Functional Theory has been used to determine the energetically preferred structures of submonolayer, monolayer, and multilayer Pt films on both ideal terminations of SrTiO 3 (1 0 0), SrTiO 3 (1 1 1), and SrTiO 3 (1 1 0). The strength of the resulting metal/metal oxide interfaces was characterized by the adsorption energy of the film and the filmÕs work of separation. The two polar surfaces, SrTiO 3 (1 1 1) and SrTiO 3 (1 1 0), form significantly stronger interfaces than the non-polar SrTiO 3 (1 0 0) surface. Approximate criteria were applied to predict the growth mode of Pt on each surface. Ó 2005 Elsevier B.V. All rights reserved. Keywords: Density functional calculations; Adhesion; Strontium titanate; Platinum; Polar surfaces 1. Introduction The heteroepitaxial growth of thin metal films on metal oxide substrates has drawn interest for potential applications in areas ranging from cata- lysis to microelectronics [1]. Control of the mor- phology and orientation of the thin metal film are often critical to these technologies. Interface strain and strength play a large role in determining heteroepitaxial film growth morphology [1–5]. The stronger the metal/metal oxide interface, the more likely epitaxial growth is to occur. The interface strength and structure for metal/metal oxide sys- tems can be obtained using Density Functional Theory (DFT), making this method a useful com- plement to experimental studies of metal film growth on metal oxides. In this paper, we present a DFT study that compares thin films of Pt on the three low index surfaces of SrTiO 3 . Two of these surfaces, SrTiO 3 (1 1 1) and SrTiO 3 (110) are polar, while the SrTiO 3 (1 0 0) surface is non-polar. To our knowledge, this is the first DFT study to 0039-6028/$ - see front matter Ó 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.susc.2005.02.033 * Corresponding author. Tel.: +1 4122684207; fax: +1 4122687139. E-mail address: sholl@andrew.cmu.edu (D.S. Sholl). Surface Science 581 (2005) 66–87 www.elsevier.com/locate/susc