UHV-STM Investigations and Numerical Calculations of a Ruthenium β-Diketonato Complex with Protected Ethynyl Ligand: [Ru(dbm) 2 (acac-TIPSA)]

Loranne Vernisse (1) , Sabrina Munery (1, 2) , Nicolas Ratel-Ramond (3) , Youness Benjalal (1) , Olivier Guillermet (1) , Xavier Bouju (1) , Roland Coratger (1) , Jacques Bonvoisin (1, 2)

1 CEMES-GNS - Groupe NanoSciences
2 International Center for Materials Nanoarchitectonics (MANA)
3 CEMES - Centre d'élaboration de matériaux et d'études structurales

The quest of molecular electronic devices necessitates addressing model molecular systems as starting points. Among the targeted functions, electron transfer between specific moieties inside a molecule is expected to play a fundamental role for ultimate logical gates. Here we propose a coordination complex exhibiting two inorganic centers (Ru and Si) that constitutes a step towards a more complex architecture. Starting from the complex 1 [Ru(dbm)2(acac-I)] (dbm = dibenzoylmethanate ion, acac-I = 3-iodo-2,4-pentanedionate ion), the complex 2 [Ru(dbm)2(acac-TIPSA)] (acac-TIPSA=3-(triisopropylsilyl)acetylene-2,4-pentanedionate ion) was obtained through Sonogashira cross coupling reaction under classical conditions. This complex 2 was characterized by elemental analysis, IR, 1H NMR, 13C NMR, UV-Vis, cyclic voltammetry, mass spectroscopy as well as X-ray single crystal diffraction. It crystallized with empirical formula of C46H49O6Ru1Si1 in a monoclinic crystal system and space group P21/c with a = 21.077(3) Å, b = 9.5130(7) Å, c = 21.8790(12) Å, beta = 94.125(7)°, V = 4375.5(7) Å3 and Z = 4. Additionally, scanning tunneling microscopy measurements at liquid He temperature and in an ultra-high vacuum (UHV-STM) were conducted on complex 2 on a Ag(111) surface. The STM images, supported by adsorption and STM image calculations, demonstrate that the molecules exist in two stable forms when adsorbed on the metallic surface.

Mots clés: Adsorption; Scanning Tunneling Microscopy; Low Temperature; Image Calculations; β-diketonato; Ultra High Vacuum; Ruthenium

Domaines: Chimie de coordination; Chimie théorique et/ou physique

Loranne Vernisse, Sabrina Munery, Nicolas Ratel-Ramond, Youness Benjalal, Olivier Guillermet, et al.. UHV-STM Investigations and Numerical Calculations of a Ruthenium β-Diketonato Complex with Protected Ethynyl Ligand: [Ru(dbm) 2 (acac-TIPSA)]. Journal of Physical Chemistry C, 2012, 116 (25), pp.13715-13721. ⟨10.1021/jp304523f⟩. ⟨hal-01737267⟩