Fluoreno[2,3-b]fluorene vs Indeno[2,1-b]fluorene: Unusual Relationship between the Number of π Electrons and Excitation Energy in m-Quinodimethane-Type Singlet Diradicaloids.
Miyoshi, Hirokazu; Miki, Masahito; Hirano, Shintaro; Shimizu, Akihiro; Kishi, Ryohei; Fukuda, Kotaro; Shiomi, Daisuke; Sato, Kazunobu; Takui, Takeji; Hisaki, Ichiro; Nakano, Masayoshi; Tobe, Yoshito; The Journal of organic chemistry 82 (2017) 1380–1388; doi:10.1021/acs.joc.6b02500

data_4032146
_publ_section_title
;
 Fluoreno[2,3-b]fluorene vs Indeno[2,1-b]fluorene: Unusual Relationship
 between the Number of \p Electrons and Excitation Energy in
 m-Quinodimethane-Type Singlet Diradicaloids.
;
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