Theoretical Study of Novel Structures of Materials by Electronic Excitation and Unified Model

电子激励和统一模型材料新型结构的理论研究

• 批准号: 07304067
• 负责人: SHINOZUKA Yuzo
• 金额: $ 1.86万
• 依托单位: Yamaguchi University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07304067/
• 关键词: electronic excitation; defect reaction; metastable structure; non-equilibrium material; structural change; relaxation dynamics; first-principle calculation; impurity defect

1) A variety of possible configurations of metastable structures has been calculated and proposed for s-p bonding materials, especially on nano-size cluster systems, surfaces, point defects and amorphous states. The relations among them and also between that of bulk system are clarified. The co-doping method is proposed for p- or n-type valence control of wide gap semiconductors.2) Theories for optical processes are developed for semiconductor hetero interfaces and surfaces, and for one-dimensional and mesoscopic organic materials.3) A general theory is proposed for the transition of electronic-atomic systems both describing the static limit (tunnel process) and the dynamical limit (level crossing). The mechanisms are proposed for the desorptin of an adatom on a semiconductor surface and also for the atom manipulation by a tip of STM.4) Nonmetallic crystalline materials are classified into five types, F,SI,SII,SIII,and U,according to the character of a relaxd photo-created exciton, the degree of the lattice relaxation and the way of exciton annihilation.In order to understand completely the structural change by electronic excitation in condensed matter, it is necessary to know (a) the character of the ground state (atomic configuration and electronic state), (b) the way of excitation (by photon or high energy particle ; valence excitation or core excitation) and the character of the electronic excited state, (c) the relaxation path in space and time and (d) the character of the relaxd excited state. The investigation of each mechanism and their unification enable us to understand deeply the bondings of condensed matter and have a guiding principle to fabricate novel structures of materials.

1)对于s-p键材料，特别是纳米团簇、表面、点缺陷和非晶态，已经计算并提出了各种可能的亚稳结构构型。阐明了它们之间的关系以及体系统之间的关系。提出了用于宽禁带半导体p型或n型价态控制的共掺杂方法。2）发展了半导体异质界面和表面以及一维和介观有机材料的光学过程理论。3）提出了描述电子-原子系统跃迁的静态极限（隧道过程）和动态极限（能级交叉）的一般理论。4）非金属晶体材料按其弛豫光生激子的性质分为F、SI、SII、SIII和U五种类型，并对它们的结构进行了讨论。为了更好地理解电子激发引起的结构变化，在凝聚态中，必须知道（a）基态的特征（原子组态和电子态），（B）激发方式（光子或高能粒子;价激发或芯激发）和电子激发态的特征，（c）空间和时间中的弛豫路径和（d）弛豫激发态的特征。对每种机制的研究及其统一使我们能够深入理解凝聚态物质的成键，并为制造新的材料结构提供指导原则。

项目成果

T.Uda: "Electronic and Optical Properties of Hydrogenated Silicon Clusters." Surface Reviews and Letters. Vol.3. 127 (1996)

T.Uda：“氢化硅簇的电子和光学特性。”

S.Saito: "Electronic Structure of Si20 Fullerene and Solid Si20" Surf.Rev.Lett.Vol.3. 721-728 (1996)

S.Saito：“Si20 富勒烯和固体 Si20 的电子结构”Surf.Rev.Lett.Vol.3。

H.Sumi: "Electron Transfer via a Midway Molecule as Seen in Primary Processes in Photosynthesis ; Superexchange or Sequential,or Unified ?" Adriatico Research Conference on Electron and Ion Transfer in Condensed Media. (1996)

H.Sumi：“光合作用初级过程中通过中途分子进行的电子转移；超级交换、顺序还是统一？”

Y.Okamoto: "Fist-principles Calculations on Mg Impurity and Mg-H Complex in GaN." Jpn.J.Appl.Phys.Vol.35. L807-L809 (1996)

Y.Okamoto：“GaN 中 Mg 杂质和 Mg-H 络合物的第一性原理计算”。

S.Abe: "Optical and Dynamical Properties of One-Dimensional Excitons in Conjugated Polymers" Materials and Measurements in Molecular Electronics (Springer Proceedings in Physics). 81. 85-95 (1996)

S.Abe：“共轭聚合物中一维激子的光学和动力学特性”分子电子学中的材料和测量（施普林格物理学报）。