Observations of Mixed-Valence Di- and Trinuclear Organometallic

Complexes on a Au(111) Surface

Rebecca C. QuardokusNatalie A. Wasio

Bi- and Trinuclear Organometallic Molecules

Trans-[Cl(dppe)2Ru(C≡C)6Ru(dppe)2Cl]

“Ru2”

{Cp*(dppe)Fe(CC-)}2(1,3-C6H4)

“m-Fe2”

{Cp*(dppe)Fe(CC-)}2(1,4-C6H4)

“p-Fe2”

{Cp*(dppe)Fe(CC-)}2(1,3,5-C6H4)

“Fe3”

Neutral Molecules

Oxidation Reaction

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Mixed-Valence Molecules

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Mixed-Valence Molecules

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Quantum Cellular Automata

Show Movie

Study Single Molecules on a Surface

• Use STM to study the properties of single molecules on the surface.

• Do single molecules on a surface possess the same electronic properties as solvated ensembles?

Scanning Tunneling Microscopy

• How do we get information about the electron density on the surface?

A. M. Moore, P. S. Weiss, Annual Review of Analytical Chemistry, 1, 857-882, (2008).

Previous WorkNeutral Ru2

250 Åｘ 180 ÅMixed-Valence Ru2

110 Åｘ 105 Å

meta-Fe2

66 Åｘ 61 Å175 Åｘ 179 Å

Neutral

Mixed Valence

C-DFT Calculations for MV meta-Fe2

66 Åｘ 61 Å

Experimental STM imageTheoretical STM images

para-Fe2

137 Åｘ 122 Å

498 Åｘ 340 Å

Neutral

Mixed Valence

54 Åｘ 48 Å

Mixture of meta-Fe2 and para-Fe2

Unoccupied orbitals Occupied orbitals

162 Åｘ 159 Å 162 Åｘ 159 Å

m-Fe2

p-Fe2

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Fe3

Proposed Work•Fe3+

•Fe32+

•Study occupied and unoccupied orbitals

Neutral Fe3, 187 Åｘ 91 Å

Neutral Fe3, 81 Åｘ 58 Å

Moving Molecules

269 Åｘ 51 Å

269 Åｘ 55 Å

269 Åｘ 69 Å

Proposed WorkStudy influences of neighboring molecules

Thank You

• Dr. S. Alex Kandel

• Dr. J. Dan Gezelter

• Dr. Prashant V. Kamat

• Dr. Marya Lieberman

• The Kandel Lab

Mixed-Valence p-Fe2

488 Åｘ 177 Å

355 Å x 137 Å

Mixed-Valence m-Fe2

230 Åｘ 170 Å

Neutral m-Fe2

398 Åｘ 367 Å

335 Åｘ 323 Å

210 Åｘ 158 Å

Previous Work on Fe2

• X-ray Crystallography

• Infrared Spectroscopy

• Mössbauer Spectroscopy

• Electron Spin Resonance

• UV-Vis Spectroscopy

• Density Functional Molecular Orbital Calculation