Atomic scale imaging, manipulation, and spectroscopy

POSTDOC: Byoung Choi, Franck Rose, Sabine Maier
STUDENTS: Mous Tatarkhanov, Ingeborg Stass, Yu Shi
Former Researchers: Tomoko Shimizu, Aitor Mugarza and Evgeny Fomin

Individual atoms and molecules are manipulated with the help of a scanning tunneling and atomic force microscopes (STM, AFM) that operate at cryogenic temperatures (~20-30 K). Manipulation consists of moving atoms and molecules from one position to another, and the formation and dissociation of single molecular bonds. The manipulation mechanisms include electronic, vibrational and rotational excitation of molecules by the STM tip. Our goal is to understand the basic science behind these processes. Inorganic monolayers (carbon, sulfur, oxygen, etc.) and simple molecules (water, CO, NO, etc.) on surfaces are studied.

Mechanical and electrical properties of molecules in self-assembled films

POSTDOC: Bas Hendriksen
STUDENTS: Yabing Qi, Florent Martin

Systems studied include organic monolayers that are model lubricants, for example, self-assembled monolayers of alkylthiols, alkylsilanes, alkylamines and others in air or controlled environments.

Ambient Pressure Photoelectron Spectroscopy for Environmental Sciences

POSTDOCS: Xingyi Deng, Tirma Herranz-Cruz
Former Researcher:Guido Ketteler

We have built a unique environmental chamber that allows us to perform X-ray photoelectron spectroscopy under thermodynamic equilibrium conditions between the surface and gases at pressures in the atmospheric range. These experiments are carried out at the Berkeley Lab Synchrotron (the Advanced Light Source). We have used this instrument in studies of the melting of ice, the adsorption and dissolution of alkali halides by water, and other problems in the environmental sciences. Other applications include the study of catalyst surfaces in situ, i.e. as the reaction is proceeding. 

Studies of friction, adhesion, and wear at nanometer scale

Former Researchers: Jeong Young Park (Now in Prof. Somorjai Group) and Christoph Weiss

Friction, adhesion and wear in nanometer size contacts that involve a finite number of atoms and molecules (from tens to thousands) are studied using atomic force microscopes. The studies are aimed at understanding the mechanisms of energy dissipation and wear. 

Electronic, mechanical, and chemical properties of nanoclusters

Former Researcher: Sang Hoon Kim

The properties of nanoclusters are studied using AFM, Surface Forces Apparatus and X-ray adsorption and emission spectroscopies at the Berkeley Synchrotron. The studies are aimed at correlating electronic, mechanical and chemical properties with cluster size, particularly where quantum confinement effects become important in the nanometer size range. 

Structure of thin liquid films and Wetting

Postdoc: Peng Jiang

Visiting Professor: Kenta Arima

Former Researcher: Albert Verdaguer

We study the structure of liquids at the nanometer scale in thin films and droplets. Our goal is to understand at the molecular level the phenomena of wetting and lubrication. The studies are performed with the help of atomic force microscopes (AFM) that operate in a non-contact mode, to avoid pertubation of the liquid surface by the tip. Other studies are performed using spectroscopic methods, such as vibrational and photoelectron spectroscopy. 

Nano Scale Materials Imaging and Manipulation (Molecular Foundry)

ACTING FACILITY DIRECTOR: D. Frank Ogletree

STAFF SCIENTIST: Paul Ashby

STAFF SCIENTIST: Jim Schuck

Catalytic and chemical properties of surfaces

POSTDOC: Feng Tao
STUDENTS:Max Montano (recently graduated), Derek Butcher (Collaboration work with Prof. Gabor Somorjai, Dept. Chemistry, UC Berkeley)

Our catalysis and surface chemistry studies are aimed at determining the adsorption geometry of atoms and molecules on catalyst surfaces, and their reaction pathways. STM and photoelectron spectroscopy techniques are used in vacuum and under high pressure to provide atomically resolved images of the surfaces.