| Project/Area Number |
15350018
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Physical chemistry
|
|---|
| Research Institution | NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY |
|---|
Principal Investigator |
SUZUKI Isao H. National Institute of Advanced Industrial Science and Technology, National Metrology Institute, Head of Division, 計測標準研究部門, 科長 (70357284)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
SAITO Norio National Institute of Advanced Industrial Science and Technology, National Metrology Institute, Senior Researcher, 計測標準研究部門, 主任研究員 (80344191)
UEDA Kiyoshi Tohoku University, Institute of Multidisciplinary Research for Advanced Materials, Professor, 多元物質科学研究所, 教授 (50151791)
|
|---|
| Project Period (FY) |
2003 – 2004
|
| Project Status |
Completed (Fiscal Year 2004)
|
| Budget Amount *help |
¥14,800,000 (Direct Cost: ¥14,800,000)
Fiscal Year 2004: ¥2,300,000 (Direct Cost: ¥2,300,000)
Fiscal Year 2003: ¥12,500,000 (Direct Cost: ¥12,500,000)
|
|---|
| Keywords | Electron-ion multi-coincidence detection / Momentum imaging / Inner-shell photoionization / Shape resonance / Ultra-fast time detection / Small molecule / Vibrational structure / Molecular beam / 内殻励起 / 内殻イオン化 / 二酸化炭素 |
|---|
| Research Abstract |
We have developed a multiple electron-ion-coincidence momentum imaging apparatus with high momentum resolution using monochromatized undulator radiation at SPring-8, in order to study K-shell photoelectron angular distribution(PAD) in the molecular frame. This apparatus consists of electron and ion time-of-flight spectrometers with multi-hit two-dimensional position sensitive detectors, a supersonic jet of samples, and a fast TDC system, which is composed of 12 bits/100 MHz crystal oscillator counters and 7 time-to-amplitude converters and can receive signals up to 6 as start pulses and one signal as a stop signal. The time resolution of this TDC is about 120 ps under the time spam of 40 μs. Using this apparatus we have measured vibration-resolved photoelectron angular distributions of molecules in the molecular frame and clarified the vibration-resolved O 1s PADs from CO_2 in the O 1s→5σ_g^* shape resonance region. The PADs are compared with the theoretical calculation using a partial
… More
ly relaxed Hartree-Fock approximation, which elucidated a role of partial wave components in the anti-symmetric-stretching vibrational mode signals for photoelectron emission. Then, we have measured vibration- and multiplet-resolved N 1s PADs from NO in the N 1s→σ^* shape resonance region. There are two maxima in the N 1s ionization region of NO, around 413 and 415 eV, which were interpreted as σ^* shape resonance, shake up, shake off, or exchange splitting. It has been found very interesting to compare the PADs around the two maxima each other, which are giving fruitful information on electron emission mechanisms from the K-shell of small molecules. Further this apparatus has served for clarification of molecular deformation just before ionic decomposition following K-shell excitation and/or ionization in small molecules like CO_2,C_2H_2 and NO_2.
In conclusion, we have developed the multi-coincidence momentum imaging apparatus for obtaining the photoelectron angular distributions with vibrational resolution in the molecular frame and clarified detailed mechanisms of photoelectron emission processes in the K-shell electrons of small molecules. Less
|
