title: Stable neutral radicals of planar N2O2-type dipyrrin platinum complexes: hybrid radicals of the delocalized organic π-orbital and platinum d-orbital.
abstract: Neutral radicals of N2O2-dipyrrin platinum complexes were synthesized by the reaction of dipyrrin ligands with PtCl2(cod) and successive one-electron oxidation. The radicals are very stable even under aerobic and ambient conditions. X-ray crystallographic analysis revealed the stacking array of the planar dipyrrin complex moieties. The ESR signals were broadened and significantly downfield shifted. The absorption spectra exhibited NIR bands. These results indicated a delocalized radical character with a contribution by the platinum d-orbital.
authors.affiliation: Graduate School of Pure & Applied Sciences, Tsukuba Research Center for Interdisciplinary Materials Science (TIMS), University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki 305-8571, Japan. nabesima@chem.tsukuba.ac.jp.
authors.forename: M
authors.initials: M
authors.lastname: Yamamura
authors.affiliation: Graduate School of Pure & Applied Sciences, Tsukuba Research Center for Interdisciplinary Materials Science (TIMS), University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki 305-8571, Japan. nabesima@chem.tsukuba.ac.jp.
authors.forename: H
authors.initials: H
authors.lastname: Takizawa
authors.affiliation: Graduate School of Pure & Applied Sciences, Tsukuba Research Center for Interdisciplinary Materials Science (TIMS), University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki 305-8571, Japan. nabesima@chem.tsukuba.ac.jp.
authors.forename: Y
authors.initials: Y
authors.lastname: Gobo
authors.affiliation: Graduate School of Pure & Applied Sciences, Tsukuba Research Center for Interdisciplinary Materials Science (TIMS), University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki 305-8571, Japan. nabesima@chem.tsukuba.ac.jp.
authors.forename: T
authors.initials: T
authors.lastname: Nabeshima