Closed-shell and open-shell dual nature of singlet diradical compounds

Kubo, Takashi

doi:https://doi.org/10.1515/pac-2023-0114

Closed-shell and open-shell dual nature of singlet diradical compounds

Kubo, Takashi

Pure and Applied Chemistry, 2023, 1-13

アクセス数:361件（2025-09-01 21:49 集計）

固定URL: https://hdl.handle.net/11094/91315

閲覧可能ファイル

ファイル	フォーマット	利用条件	サイズ	閲覧回数	利用開始日	説明	information
PureApplChem_20230307	pdf	なし	2.49 MB	94	2024.03.07

論文情報

ファイル出力 EndNote Basic出力 Mendeley出力

タイトル	Closed-shell and open-shell dual nature of singlet diradical compounds
著者	NRID 1000060324745 1000060324745 ORCID 0000-0001-6809-7396 0000-0001-6809-7396 researchmap permalink read0076571 read0076571 Scopus Author ID 55576439300 55576439300 著者名 Kubo, Takashi
キーワード等	closed-shell and open-shell dual nature
	coexistence of covalent bonding interaction
	cycloaddition reaction
	diradicaloid
	ICPOC-25
	one-dimensional stack
	singlet diradical
	π-dimer
内容	The final publication is available at https://doi.org/10.1515/pac-2023-0114
抄録	Unlike triplet diradicals, singlet diradicals can vary in diradical character from 0 % to 100 % depending on linker units that allow two formally unpaired electrons to couple covalently. In principle, the electronic structure of singlet diradicals can be described as a quantum superposition of closed-shell and open-shell structures. This means that, depending on the external environment, singlet diradicals can behave as either closed-shell or open-shell species. This paper summarizes our progress in understanding the electronic structure of π-conjugated singlet diradical molecules in terms of closed-shell and open-shell dual nature. We first discuss the coexistence of intra- and intermolecular covalent bonding interactions in the π-dimer of a singlet diradical molecule. The intra- and intermolecular coupling of two formally unpaired electrons are related to closed-shell and open-shell nature of singlet diradical, respectively. Then we demonstrate the coexistence of the covalent bonding interactions in the one-dimensional stack of singlet diradical molecules having different diradical character. The relative strength of the interactions is varied with the magnitude of singlet diradical index y0. Finally, we show the dual reactivity of a singlet diradical molecule, which undergoes rapid [4 + 2] and [4 + 4] cycloaddition reactions in the dark at room temperature. Closed-shell and open-shell nature endow the singlet diradical molecule with the reaction manner as diene and diradical species, respectively.
会議情報	会議名 International Conference on Physical Organic Chemistry 回次 25 主催機関 International Union of Pure and Applied Chemistry 開催期間 July 10th to July 15th, 2022 開催地 Hiroshima 開催国日本
出版者	De Gruyter Open Ltd
収録物名	Pure and Applied Chemistry
ページ	1-13
刊行年月	2023-03-07
言語	英語
ハンドルURL	https://hdl.handle.net/11094/91315
PISSN	00334545
eISSN	13653075
NCID	AA00797859
関連情報 (isIdenticalTo)	DOI (出版社版) https://doi.org/10.1515/pac-2023-0114
アクセス権	open access
出版タイプ	Version of Record
カテゴリ	会議発表論文 Conference Paper

資源タイプ	会議発表論文
ローカル資源タイプ	会議発表論文
DCMI資源タイプ	text
DCTERMS.bibliographicCitation	Pure and Applied Chemistry. 2023, p. 1-13
DC.title	Closed-shell and open-shell dual nature of singlet diradical compounds
DC.creator	Kubo, Takashi
DC.publisher	De Gruyter Open Ltd
DC.language' scheme='DCTERMS.RFC1766	英語
DC.type' scheme='DCTERMS.DCMIType	text
DCTERMS.issued' scheme='DCTERMS.W3CDTF	2023-03-07
DC.identifier	https://doi.org/10.1515/pac-2023-0114
DC.subject	closed-shell and open-shell dual nature
	coexistence of covalent bonding interaction
	cycloaddition reaction
	diradicaloid
	ICPOC-25
	one-dimensional stack
	singlet diradical
	π-dimer
DC.description	The final publication is available at https://doi.org/10.1515/pac-2023-0114
DCTERMS.abstract	Unlike triplet diradicals, singlet diradicals can vary in diradical character from 0 % to 100 % depending on linker units that allow two formally unpaired electrons to couple covalently. In principle, the electronic structure of singlet diradicals can be described as a quantum superposition of closed-shell and open-shell structures. This means that, depending on the external environment, singlet diradicals can behave as either closed-shell or open-shell species. This paper summarizes our progress in understanding the electronic structure of π-conjugated singlet diradical molecules in terms of closed-shell and open-shell dual nature. We first discuss the coexistence of intra- and intermolecular covalent bonding interactions in the π-dimer of a singlet diradical molecule. The intra- and intermolecular coupling of two formally unpaired electrons are related to closed-shell and open-shell nature of singlet diradical, respectively. Then we demonstrate the coexistence of the covalent bonding interactions in the one-dimensional stack of singlet diradical molecules having different diradical character. The relative strength of the interactions is varied with the magnitude of singlet diradical index y0. Finally, we show the dual reactivity of a singlet diradical molecule, which undergoes rapid [4 + 2] and [4 + 4] cycloaddition reactions in the dark at room temperature. Closed-shell and open-shell nature endow the singlet diradical molecule with the reaction manner as diene and diradical species, respectively.
DC.format	91315
citation_title	Closed-shell and open-shell dual nature of singlet diradical compounds
citation_author	Kubo, Takashi
citation_publisher	De Gruyter Open Ltd
citation_language	英語
citation_date	2023-03-07
citation_journal_title	Pure and Applied Chemistry
citation_firstpage	1
citation_lastpage	13
citation_doi	https://doi.org/10.1515/pac-2023-0114
citation_public_url	https://hdl.handle.net/11094/91315

Closed-shell and open-shell dual nature of singlet diradical compounds

閲覧可能ファイル

論文情報

論文詳細を表示