{"_buckets": {"deposit": "428997ce-42ec-40dd-a489-b8afaf05f4fc"}, "_deposit": {"created_by": 21, "id": "1463", "owners": [21], "pid": {"revision_id": 0, "type": "depid", "value": "1463"}, "status": "published"}, "_oai": {"id": "oai:ir.soken.ac.jp:00001463", "sets": ["9"]}, "author_link": ["0", "0", "0"], "item_1_biblio_info_21": {"attribute_name": "書誌情報（ソート用）", "attribute_value_mlt": [{"bibliographicIssueDates": {"bibliographicIssueDate": "2009-03-24", "bibliographicIssueDateType": "Issued"}, "bibliographic_titles": [{}]}]}, "item_1_creator_2": {"attribute_name": "著者名", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "岩佐, 豪"}], "nameIdentifiers": [{"nameIdentifier": "0", "nameIdentifierScheme": "WEKO"}]}]}, "item_1_creator_3": {"attribute_name": "フリガナ", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "イワサ, タケシ"}], "nameIdentifiers": [{"nameIdentifier": "0", "nameIdentifierScheme": "WEKO"}]}]}, "item_1_date_granted_11": {"attribute_name": "学位授与年月日", "attribute_value_mlt": [{"subitem_dategranted": "2009-03-24"}]}, "item_1_degree_grantor_5": {"attribute_name": "学位授与機関", "attribute_value_mlt": [{"subitem_degreegrantor": [{"subitem_degreegrantor_name": "総合研究大学院大学"}]}]}, "item_1_degree_name_6": {"attribute_name": "学位名", "attribute_value_mlt": [{"subitem_degreename": "博士（理学）"}]}, "item_1_description_1": {"attribute_name": "ID", "attribute_value_mlt": [{"subitem_description": "2009011", "subitem_description_type": "Other"}]}, "item_1_description_12": {"attribute_name": "要旨", "attribute_value_mlt": [{"subitem_description": "The aim of this thesis is to theoretically study geometric, electronic, and optical prop-\u003cbr /\u003eerties of one-nanometer sized cluster compounds. The thesis is composed of two parts.\u003cbr /\u003e In the first part, the geometric and electronic properties of gold-thiolate cluster com-\u003cbr /\u003epounds, which have recently been studied experimentally, are revealed. I will discuss\u003cbr /\u003ehow the local geometric structures are related to the electronic properties of the com-\u003cbr /\u003epounds. In the second part, optical response theory that is applicable to the nan-\u003cbr /\u003eocluster compounds is developed. Special emphasis is placed on nonuniform electronic\u003cbr /\u003eexcitations induced by near-fields.\u003cbr /\u003e　　Let me briefly review history of metal nanoclusters. Research in nanocluster com-\u003cbr /\u003epounds has its root on the study of bare metal clusters in gaseous phase, where size-\u003cbr /\u003edependent physicochemical properties are the main concern. However, most of these\u003cbr \u003e bare clusters are energetically and chemically unstable. In the past few decades,\u003cbr /\u003emetal clusters protected by organic molecules have been synthesized in solution, and\u003cbr /\u003esome of these cluster compounds were found to be stable even in the air.　Although\u003cbr /\u003ethese nanocluster compounds were expected to be promising candidates for functional\u003cbr /\u003enanomaterials in a wide range of nanotechnologies, it is not trivial to characterize their\u003cbr /\u003edetailed structures. Reducing the size of clusters to the 1 nm scale, their geometries\u003cbr /\u003eand other properties become much more sensitive to the change in size and chemical\u003cbr /\u003ecompositions. In such circumstances, sub-nanometer sized gold-cluster compounds\u003cbr /\u003ehave intensively been synthesized with the definitive determination on the chemical\u003cbr /\u003ecompositions. Despite the brilliant results, even their geometrical structures have not\u003cbr /\u003esufficiently been characterized. Furthermore, the studies on their optical properties\u003cbr /\u003eare still in the juvenile stage. For these reasons, I theoretically study the geometric,\u003cbr /\u003eelectronic, and optical properties of some representative cluster compounds at the 1 \u003cbr /\u003enm scale.\u003cbr /\u003e　　The geometric and electronic structures of a gold-methanethiolate [Au\u003csmall\u003e25\u003c/small\u003e(SCH\u003csmall\u003e3\u003c/small\u003e)\u003csmall\u003e18\u003c/small\u003e]\u003csup\u003e+\u003c/sup\u003e\u003cbr /\u003eare investigated by carrying out the density functional theory (DFT) calculations.\u003cbr /\u003eThe obtained optimized structure consists of a planar Au\u003csmall\u003e7\u003c/small\u003e core cluster and Au-S com-\u003cbr /\u003eplexes, where the Au\u003csmall\u003e7\u003c/small\u003e plane is enclosed by a Au\u003csmall\u003e12\u003c/small\u003e(SCH\u003csmall\u003e3\u003c/small\u003e)\u003csmall\u003e12\u003c/small\u003e ring and sandwiched by two\u003cbr /\u003eAu\u003csmall\u003e3\u003c/small\u003e(SCH\u003csmall\u003e3\u003c/small\u003e)\u003csmall\u003e3\u003c/small\u003e ring clusters. This geometry differs in shape and bonding from a gener-\u003cbr /\u003eally accepted geometrical motif of gold-thiolate clusters that a spherical gold cluster is\u003cbr /\u003esuperficially ligated by thiolate molecules. This newly optimized gold-methanthiolate\u003cbr /\u003ecluster shows a large HOMO-LUMO gap, and calculated X-ray diffraction and absorp-\u003cbr /\u003etion spectra successfully reproduce the experimental results. On another gold cluster\u003cbr /\u003ecompound [Au\u003csmall\u003e25\u003c/small\u003e(PH\u003csmall\u003e3\u003c/small\u003e(SCH\u003csmall\u003e3\u003c/small\u003e)Cl\u003csmall\u003e2\u003c/small\u003e]\u003csup\u003e2+\u003c/sup\u003e, which consists of two icosahedral Au\u003csmall\u003e13\u003c/small\u003e clus-\u003cbr /\u003eters bridged by methanethiolates sharing a vertex gold atom and terminated by chlo-\u003cbr /\u003erine atoms, the DFT calculation provides very close structure to the experimentally\u003cbr /\u003eobtained gold cluster [Au\u003csmall\u003e25\u003c/small\u003e(PPh\u003csmall\u003e3\u003c/small\u003e)\u003csmall\u003e10\u003c/small\u003e(SC\u003csmall\u003e2\u003c/small\u003eH\u003csmall\u003e5\u003c/small\u003e)\u003csmall\u003e5\u003c/small\u003eCL\u003csmall\u003e2\u003c/small\u003e]\u003csup\u003e2+\u003c/sup\u003e. I further demonstrate that a\u003cbr /\u003evertex-sharing triicosahedral gold cluster [Au\u003csmall\u003e37\u003c/small\u003e(PH\u003csmall\u003e3\u003c/small\u003e)\u003csmall\u003e10\u003c/small\u003e(SCH\u003csmall\u003e3\u003c/small\u003e)\u003csmall\u003e10\u003c/small\u003eCl\u003csmall\u003e2\u003c/small\u003e]\u003csup\u003e+\u003c/sup\u003e is also achieved\u003cbr /\u003eby bridging the core Au\u003csmall\u003e13\u003c/small\u003e units with the methanethiolates. A comparison between\u003cbr /\u003ethe absorption spectra of the bi- and triicosahedral clusters shows that the new elec-\u003cbr /\u003etronic levels due to each oligomeric structure appear sequentially, whereas other elec-\u003cbr /\u003etronic properties remain almost unchanged compared to the individual icosahedral\u003cbr /\u003eAu\u003csmall\u003e13\u003c/small\u003e cluster. These theoretical studies have elucidated the fundamental properties of\u003cbr /\u003ethe promising building blocks such as geometric structures and stability of real cluster\u003cbr /\u003ecompounds in terms of the detailed electronic structures. As a next step, I have to gain\u003cbr /\u003ea further insight into the dynamical optical properties of cluster compounds. In partic-\u003cbr /\u003eular for discussing photoinduced dynamics in nanoclusters or nanocluster assemblies,\u003cbr /\u003einter-cluster near-field interactions should be understood properly. The conventional\u003cbr /\u003elight-matter interaction based on available lasers is quite different from the near-field\u003cbr /\u003einteraction. The electric fields of available lasers usually have the wavelength much\u003cbr /\u003elonger than the size of the local structure of the cluster compounds. In other words,\u003cbr /\u003ethe 1-nm-sized cluster compounds feel the almost uniform electromagnetic field and\u003cbr /\u003ethus the local structures of the compounds cannot be resolved. In contrast, a near-field\u003cbr /\u003einteraction occurs at the same scale of the cluster compounds and is thus expected to\u003cbr /\u003ebe used to observe the local structure of the 1 nm sized materials. The difficulty in\u003cbr /\u003etheir theoretical description arises from the fact that the near-field has a non-uniform\u003cbr /\u003elocal structure. For these reasons, I will develop an optical response theory that is\u003cbr /\u003eapplicable to 1-nm-sized clusters interacting with the near-field.\u003cbr /\u003e　　The optical response theory is developed in a general form on the basis of the\u003cbr /\u003emultipolar Hamiltonian derived from the minimal coupling Hamiltonian by a canon-\u003cbr /\u003eical transformation. The light-matter interaction in the multipolar Hamiltonian is\u003cbr /\u003edescribed in terms of the space integral of inner product of polarization and electric\u003cbr /\u003efield. whereas the minimal coupling Hamiltonian uses momentum and vector poten-\u003cbr /\u003etial, which are rather inconvenient for practical computations. Noteworthy is the fact\u003cbr /\u003ethat the polarization in the integral can be treated entirely without any approxima-\u003cbr /\u003etions. This means an infinite order of multipole moments is taken into account. Thus\u003cbr /\u003ethe present approach is a generalization of the optical response formulation beyond\u003cbr /\u003ethe dipole approximation. I have incorporated the optical response theory with the\u003cbr /\u003enonuniform light-matter interaction into an electron-dynamics simulation approach\u003cbr /\u003ebased on the time-dependent density functional theory (TDDFT) in real space. To \u003cbr /\u003eelucidate the electron dynamics of 1 nm-sized molecules induced by the nonuniform\u003cbr /\u003elight-matter interaction, the integrated TDDFT approach has been applied to and\u003cbr /\u003ecomputationally solved for a test molecular system, NC\u003csmall\u003e6\u003c/small\u003eN, in the dipole radiation\u003cbr /\u003efield. Several unprecedented electronic excitation modes were induced owing to the\u003cbr /\u003enonuniform light-matter interaction using the near-field in contrast to the uniform\u003cbr /\u003elight-matter interaction that corresponds to the conventional dipole approximation.\u003cbr /\u003eFor example, high harmonics were generated more easily. It has also been found that\u003cbr /\u003ethe near-field with different phase and spatial structure promotes or suppresses high\u003cbr /\u003eharmonics.\u003cbr /\u003e　　In conclusion, I have revealed the geometric and electronic properties of gold-\u003cbr /\u003ethiolate nanocluster compounds and developed optical response theory in an effort\u003cbr /\u003eto understand nonuniform light-matter interaction between near-filed and 1 nm-sized\u003cbr /\u003ecluster compounds.", "subitem_description_type": "Other"}]}, "item_1_description_18": {"attribute_name": "フォーマット", "attribute_value_mlt": [{"subitem_description": "application/pdf", "subitem_description_type": "Other"}]}, "item_1_description_7": {"attribute_name": "学位記番号", "attribute_value_mlt": [{"subitem_description": "総研大甲第1219号", "subitem_description_type": "Other"}]}, "item_1_select_14": {"attribute_name": "所蔵", "attribute_value_mlt": [{"subitem_select_item": "有"}]}, "item_1_select_16": {"attribute_name": "複写", "attribute_value_mlt": [{"subitem_select_item": "複写不可"}]}, "item_1_select_17": {"attribute_name": "公開状況", "attribute_value_mlt": [{"subitem_select_item": "全文公開可"}]}, "item_1_select_8": {"attribute_name": "研究科", "attribute_value_mlt": [{"subitem_select_item": "物理科学研究科"}]}, "item_1_select_9": {"attribute_name": "専攻", "attribute_value_mlt": [{"subitem_select_item": "07 構造分子科学専攻"}]}, "item_1_text_10": {"attribute_name": "学位授与年度", "attribute_value_mlt": [{"subitem_text_value": "2008"}]}, "item_creator": {"attribute_name": "著者", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "IWASA, Takeshi", "creatorNameLang": "en"}], "nameIdentifiers": [{"nameIdentifier": "0", "nameIdentifierScheme": "WEKO"}]}]}, "item_files": {"attribute_name": "ファイル情報", "attribute_type": "file", "attribute_value_mlt": [{"accessrole": "open_date", "date": [{"dateType": "Available", "dateValue": "2016-02-17"}], "displaytype": "simple", "download_preview_message": "", "file_order": 0, "filename": "甲1219_要旨.pdf", "filesize": [{"value": "396.0 kB"}], "format": "application/pdf", "future_date_message": "", "is_thumbnail": false, "licensetype": "license_11", "mimetype": "application/pdf", "size": 396000.0, "url": {"label": "要旨・審査要旨", "url": "https://ir.soken.ac.jp/record/1463/files/甲1219_要旨.pdf"}, "version_id": "e4d1ecbc-d5ac-41df-b74d-040310b4a80a"}, {"accessrole": "open_date", "date": [{"dateType": "Available", "dateValue": "2016-02-17"}], "displaytype": "simple", "download_preview_message": "", "file_order": 1, "filename": "甲1219_本文.pdf", "filesize": [{"value": "3.7 MB"}], "format": "application/pdf", "future_date_message": "", "is_thumbnail": false, "licensetype": "license_11", "mimetype": "application/pdf", "size": 3700000.0, "url": {"label": "本文", "url": "https://ir.soken.ac.jp/record/1463/files/甲1219_本文.pdf"}, "version_id": "da16abfb-3d95-4bad-b3ab-dd32bbdb4bd8"}]}, "item_language": {"attribute_name": "言語", "attribute_value_mlt": [{"subitem_language": "eng"}]}, "item_resource_type": {"attribute_name": "資源タイプ", "attribute_value_mlt": [{"resourcetype": "thesis", "resourceuri": "http://purl.org/coar/resource_type/c_46ec"}]}, "item_title": "Theoretical Investigations of Cluster Compounds on the 1 nm Scale: Geometric, Electronic, and Optical Properties", "item_titles": {"attribute_name": "タイトル", "attribute_value_mlt": [{"subitem_title": "Theoretical Investigations of Cluster Compounds on the 1 nm Scale: Geometric, Electronic, and Optical Properties"}, {"subitem_title": "Theoretical Investigations of Cluster Compounds on the 1 nm Scale: Geometric, Electronic, and Optical Properties", "subitem_title_language": "en"}]}, "item_type_id": "1", "owner": "21", "path": ["9"], "permalink_uri": "https://ir.soken.ac.jp/records/1463", "pubdate": {"attribute_name": "公開日", "attribute_value": "2010-03-25"}, "publish_date": "2010-03-25", "publish_status": "0", "recid": "1463", "relation": {}, "relation_version_is_last": true, "title": ["Theoretical Investigations of Cluster Compounds on the 1 nm Scale: Geometric, Electronic, and Optical Properties"], "weko_shared_id": -1}