Time-resolved Spectroscopic Studies on the basic Photo-induced Processes in C_<60> Single Crystals

C_<60>单晶基本光致过程的时间分辨光谱研究

• 批准号: 11440096
• 负责人: KAN'NO Ken-ichi
• 金额: $ 9.34万
• 依托单位: Department of Materials Science and chemistry, Faculty of Systems Engineering, Wakayama University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11440096/
• 关键词: fullerene; carbon cluster; photo-polymezation; structural change; photoluminescence; absorption edge; photoconductivity; Raman scattering; フレンケル励起子; ナノクラスター; アーバックテール; 光誘起固相重合; 光物性; ルミネッセンス

Photoluminescence and near-band-edge electronic structure of pristine C_<60> single crystals have been investigated in the low temperature phase below 90K. By applying two-photon excitation spectroscopy, a monomorphic spectrum is extracted from the several crystals which exhibit apparent diversity for ordinary one-photon excitation. Also, a localized absorption band with discrete vibronic sub-peaks is clearly confirmed at 1.685 eV below the fundamental absorption edge (1.815 eV). Overall features of the luminescence-line-narrowing spectrum obtained by site-selective excitation into the localized absorp tion band are assigned to the vibronic progressions coupled with the Raman-active gerade-symmetry modes of individual C60 molecules (i.e., eight h_g, two a_g, and their combinations), accompanied by phonon-side-bands due to cooperative librations and intermolecular translations. The origin of photo luminescence and its relaxtion kinetics are fully discussed in connection with the inhomogeneously broadened localized states which are presumably due to perturbed Frenkel excitons stabilized with symmetry-lowering by adjacent intrinsic defect or some lattice disorder.

在90K以下的低温相研究了原始的C&lt；60&gt；单晶的光致发光和近带边电子结构。通过应用双光子激发光谱，从几个与普通单光子激发表现出明显多样性的晶体中提取了单态光谱。此外，在基波吸收边(1.685 eV)以下的1.685 eV处清楚地证实了具有离散振动子峰的局域吸收带。通过位置选择性激发进入局域吸收带而获得的发光线窄化光谱的总体特征被归结为与单个C60分子(即8个h_g、2个a_g及其组合)的喇曼活性激射对称模耦合的振动级数，并伴随着由于合作振动和分子间平移而产生的声子边带。结合非均匀展宽的局域态，充分讨论了光致发光的起源及其驰豫动力学，这些局域态可能是由于受扰动的Frenkel激子被邻近的本征缺陷或某些晶格无序降低而稳定的对称性降低所致。

项目成果

Ikuko Akimoto and Ken-ichi Kan'no: "Origin of intrinsic luminescence from C_<60> single crystals"Proc. XIII International Winter School '99 (API Conference Proceedings). 486. 7-10 (2000)

Ikuko Akimoto 和 Ken-ichi Kanno：“C_<60> 单晶的本征发光的起源”Proc。

Chihiro Itoh,m Masanobu Shirai, Koichiro Tanaka and Ken-ichi Kan'no: "Pulsed-ESR study of spin solitos as a probe of neutral-to-ionic phase transition of TTF-CA single crystal"Phase Transition. (in press). (2002)

Chihiro Itoh、M Masanobu Shirai、Koichiro Tanaka 和 Ken-ichi Kanno：“自旋孤子的脉冲 ESR 研究作为 TTF-CA 单晶中性到离子相变的探针”相变。

秋元郁子, 小柳孝仁, 神野賢一: "C_<60>単結晶における吸収端電子構造と「光伝導異常」"日本物理学会第57回年次大会概要集. 第57巻第1号第4分冊(26pXN-3). 797 (2002)

秋本郁子、小柳隆仁、神野健一：“C_<60>单晶中的吸收边电子结构和“光电导异常””日本物理学会第57届年会摘要第57卷第1期第1期。 4（26pXN-3）797（2002）。

I.Akimoto, K.Kan'no: "Origin of intrinsic luminescence from C_<60> single crystals"Proceedings XIII International Winter School '99 (API Conference). 486. 7-11 (2000)

I.Akimoto、K.Kanno：“C_<60> 单晶的内在发光的起源”第 XIII 国际冬季学校 99 会议记录（API 会议）。

Ikuko Akimoto and Ken-ichi Kan'no: "Photoluminescence and Near-Edge Optical Absorption in the Low-Temperature Phase of Pristine C_<60> Single Crystals"J. Phys. Soc. Jpn.. Vol.71, No.2. 630-643 (2002)

Ikuko Akimoto 和 Ken-ichi Kanno：“原始 C_<60> 单晶低温相中的光致发光和近边缘光学吸收”J。