1996 Fiscal Year Final Research Report Summary
Motion of individual atoms and mesoscopic structural dynamics on non-equillibrium surfaces
| Project/Area Number |
07454064
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
固体物性Ⅰ(光物性・半導体・誘電体)
|
|---|
| Research Institution | KYOTO UNIVERSITY |
|---|
Principal Investigator |
ARUGA Tetsuya Kyoto University, Graduate School of Science, Associate Professor, 大学院・理学研究科, 助教授 (70184299)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
NISHIJIMA Mitsuaki Kyoto University, Graduate School of Science, Professor, 大学院・理学研究科, 教授 (90108978)
TAKAGI Noriaki Kyoto University, Graduate School of Science, Research Associate, 大学院・理学研究科, 助手 (50252416)
|
|---|
| Project Period (FY) |
1995 – 1996
|
| Keywords | surface alloy / reaction dynamics / scanning tunneling microscope / coadsorption / structural dynamics |
|---|
| Research Abstract |
In order to realize the direct observation of the dynamic motion of individual atoms and molecules on the non-equillibrium surfaces and to understand the underlying microscopic mechanism, we have developped a new variable-temperature scanned probe microscope. In order to study further on the surface dynamics, we have also conducted thermal desorption and high-resolution electron energy loss spectroscopy to investigate the ordering in the (NO+CO) coadsorption system on the Pd (100) surface.
The scanned probe microscope developped in the present study can be operated under ultrahigh vacuum and at sample temperature from 100 to 1000K.Another important characteristic is its low-noise signal output. The vertical noise for the topographic imaging mode is 3pm (p-p), which enables the imaging of (100) and (111) surfaces of transition metals. This microscope can also be operated at tunneling current as low as 1pA, which enables imaging of low-conductivity materials such as organic crystals.
The ordering in (NO+CO) /Pd (100) coadsorption system has been studied by low-energy electron diffraction, thermal desorption and vibrational spectroscopy preparatory to the application of the scanned probe microscope. We have found that NO and CO form stable mixed ordered phases and that an explosive CO2 formation reaction undergoes in the mixed ordered phases. A kinetic Monte Carlo simulation based on a lattice-gas model has been done to quantify NO-CO intermolecular interactions.
We have also investigated on the H+H/Pd (100) reaction and found that the impinging H atoms force the preadsorbed H atoms to penetrate into Pd bulk (stamping absorption). The characteristics of the potential energy surface for the MH2 system was discussed.
|
