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

作者：Vernisse Loranne; Munery Sabrina; Ratel Ramond Nicolas; Benjalal Youness; Guillermet Olivier; Bouju Xavier; Coratger Roland; Bonvoisin Jacques^*

来源：Journal of Physical Chemistry C, 2012, 116(25): 13715-13721.

DOI：10.1021/jp304523f

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 toward 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, H-1 NMR, C-13 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 P2(1)/c with a = 21.077(3) angstrom, b = 9.5130(7) angstrom, c = 21.8790(12) angstrom, beta = 94.125(7)degrees, V = 4375.5(7) angstrom(3) and Z = 4. Additionally, scanning tunneling microscopy measurements at liquid He temperature and in an ultrahigh 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.

• 出版日期2012-6-28