- 著者
- Ishida Masahiko Takeuchi Osamu Mori Takehiko Shigekawa Hidemi
- 出版者
- American Physical Society
- 雑誌
- Physical review B (ISSN:01631829)
- 巻号頁・発行日
- vol.64, no.15, pp.153405, 2001-09
- 被引用文献数
- 9 10
In addition to the intermolecular symmetry breaking which is generally observed during the surface relaxation/reconstruction of atomic crystals, intramolecular relaxation is expected to exist in the case of molecular crystals, which was confirmed on the surface of β-(BEDT-TTF)2PF6 [BEDT-TTF is bis(ethylenedithio)tetrathiafulvalene] by using scanning tunneling microscopy (STM). Two types of molecular images obtained by STM were comprehensively explained by the spatial distributions of the highest-occupied molecular orbital calculated for the two types of the molecular structures. One is the structure appearing in the crystal that is derived from the x-ray diffraction measurement, which was used in the previous calculations to reproduce the STM images. The other is the relaxed molecular structure calculated by optimization of the molecular structure.
- 著者
- Xu Maojie Zhang Yaozhong Zhang Jing Lu Jiyun Qian Bingjian Lu Dejiong Zhang Yafei Wang Liang Chen Xiaoshuang Shigekawa Hidemi
- 出版者
- Springer
- 雑誌
- Nanoscale Research Letters
- 巻号頁・発行日
- vol.7, no.460, 2012-08
- 被引用文献数
- 3
We employ first-principles density functional theory calculations to study the surface reconstruction, energetic stability, and electronic structure of diamond C(331) surface. Spontaneous formation of graphene-like stripes on the reconstructed surface is found to occur as the surface terrace C atoms transform from sp3 to sp2 hybridization upon structural relaxation. The comparison of the calculated absolute surface energies of C(331), C(111), and C(110) surfaces demonstrates the energetic stability of the graphitic-like C(331) surface. Local density of electronic states analysis reveals the occurrence of localized electronic states near the Fermi level, which may have a significant impact on the surface conductivity.
- 著者
- Kanazawa Ken Taninaka Atsushi Takeuchi Osamu Shigekawa Hidemi
- 出版者
- American Physical Society
- 雑誌
- Physical review letters (ISSN:00319007)
- 巻号頁・発行日
- vol.99, no.21, pp.216102, 2007-11
- 被引用文献数
- 15 13
The structures of two competing phases and their interrelationship in the self-organization of glycine molecules on a Cu(100) surface were clarified. Despite their similar structural energies predicted using first-principles calculation, completely different mechanisms were found to stabilize the two phases. The balance and coordination of the two mechanisms that induce a variety of self-assembled structures in this attractive system were revealed. Furthermore, the importance of the microscopic arrangement of the molecules in designing the macroscopic electronic structures was directly demonstrated.
- 著者
- Terada Yasuhiko Yoshida Shoji Takeuchi Osamu Shigekawa Hidemi
- 出版者
- IOP Publishing
- 雑誌
- Journal of physics. Condensed matter (ISSN:09538984)
- 巻号頁・発行日
- vol.22, no.26, pp.264008, 2010-07
- 被引用文献数
- 32 25
The development of time-resolved scanning tunnelling microscopy (STM), in particular, attempts to combine STM with ultrafast laser technology, is reviewed with emphasis on observed physical quantities and spatiotemporal resolution. Ultrashort optical pulse technology has allowed us to observe transient phenomena in the femtosecond range, which, however, has the drawback of a relatively low spatial resolution due to the electromagnetic wavelength used. In contrast, STM and its related techniques, although the time resolution is limited by the circuit bandwidth (~100 kHz), enable us to observe structures at the atomic level in real space. Our purpose has been to combine these two techniques to achieve a new technology that satisfies the requirements for exploring the ultrafast transient dynamics of the local quantum functions in organized small structures, which will advance the pursuit of future nanoscale scientific research in terms of the ultimate temporal and spatial resolutions.
- 著者
- Xu Maojie Okada Arifumi Yoshida Shoji Shigekawa Hidemi
- 出版者
- American Institute of Physics
- 雑誌
- Applied physics letters (ISSN:00036951)
- 巻号頁・発行日
- vol.94, no.7, pp.073109, 2009
- 被引用文献数
- 5 7
Methods of forming various In nanostructures on Si surfaces are demonstrated. Using a high-index Si(311) surface, isolated nanotriangles and wires were grown by optimizing the deposition rate and substrate temperature. In contrast, nanodots were formed by the deposition of In on a Si(111)-In-31×31 surface at room temperature (RT) deposition. On a Si(111)-In-4×1/31×31 coexisting surface, nanowires were selectively grown in the Si(111)-In 4×1 area by RT deposition through the nucleation promoted by the boundary barrier produced by the surrounding 31×31 area. Details were studied using scanning tunneling microscopy.