4 results match your criteria: "Slovak University of Technology (FEI STU)[Affiliation]"

Most chemical reactions require activation which is conventionally supplied by heat. In stark contrast, mechanical activation by applied external forces opens intriguing novel possibilities. Here, the first direct comparison of mechanical versus thermal activation of bond breaking is provided.

View Article and Find Full Text PDF

Nanomanipulation using only mechanical energy.

Phys Rev Lett

September 2005

Center for Computational Materials Science (CCMS), Slovak University of Technology (FEI STU), Ilkovicova 3, SK-812 19, Bratislava, Slovakia.

We present the first computational study targeting the nanomanipulation capability of dynamic surface force microscopy. Using a very simple but challenging model, an antisite defect on a III-V(110) surface, we show how the defect can be manipulated in both the attractive and the repulsive modes and identify the role of the tip-sample interaction: either lowering the barriers or pushing the system over a high stress state using exclusively the mechanical energy stored in the oscillating cantilever. Our study also sheds light on other key issues, such as chemical resolution, explaining why vacancies are the only defects imaged in topography, and dissipation contrast formation, identifying a physical mechanism to explain the intriguing small shift between topographical and damping images.

View Article and Find Full Text PDF

Detaching thiolates from copper and gold clusters: which bonds to break?

J Am Chem Soc

September 2004

Center for Computational Materials Science, Slovak University of Technology (FEI STU), Ilkovicova 3, 81219, Bratislava, Slovakia.

The interaction of alkanethiolates with small coinage metal clusters of copper and gold was studied based on density functional theory with a focus on the metal-thiolate junction. Calculation of fragmentation energies indicate that for Cu(n)-thiolate (n = 1,3,5,7, and 9) there is a progressive lowering in energy for the fragmentation of the S-C bond in the thiolate from a value of 2.9 eV for n = 1 to 1.

View Article and Find Full Text PDF

Covalent and reversible short-range electrostatic imaging in noncontact atomic force microscopy.

Phys Rev Lett

November 2003

Center for Computational Materials Science (CCMS), Slovak University of Technology (FEI STU), Ilkovicova 3, SK-812 19, Bratislava, Slovakia.

We present a computational study of atomic-scale image formation in noncontact atomic force microscopy on metallic surfaces. We find two imaging scenarios: (1). atomic resolution arising due to very strong covalent tip-sample interaction exhibiting striking similarity with the imaging mechanism found on semiconductor surfaces, and (2).

View Article and Find Full Text PDF