title: Electronic structure of Co(III) doped bromo-bridged Ni complexes, [Ni1-xCox(chxn)2Br]Br2.
abstract: This article describes the electronic structure of the Co(III) doped Br bridged Ni(III) complexes, [Ni(1-x)Cox(chxn)2Br]Br2 (x = 0.01, 0.02, 0.05, and 0.11) by using a optical spectroscopy, scanning tunneling microscopy (STM), and electron spin resonance spectroscopy. In the optical reflectivity spectrum, the new band was formed at about 0.5 eV, which is reasonably recognized as the d(z2) band of doped Co(III) ions. In the STM images of [Ni(1-x)Cox(chxn)2Br]Br2, the bright spots attributable to the tunnel current from the Fermi level of the STM tip to the conduction band of the sample were observed. In addition, some brighter spots were also observed. Because the number of the brighter spots is in good agreement with that of doped Co species, the brighter spots can be assigned to doped Co(III) sites. These are reasonably explained by the tunnel current from the Fermi level of the tip to the d(z2) band of Co(III). The Curie spin concentration was gradually increased with increasing Co(III) ions, which is explained by the scissions of the S = 1/2 1D antiferromagnetic chains.
authors.affiliation: Department of Chemistry, Faculty of Science, Tohoku University & CREST(JST), Aramaki-Aza-Aoba, Sendai 980-8578, Japan.
authors.forename: Jimin
authors.initials: J
authors.lastname: Xie
authors.forename: Hashen
authors.initials: H
authors.lastname: Wu
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kawakami
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Iguchi
authors.forename: Shinya
authors.initials: S
authors.lastname: Takaishi
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yamashita
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Matsuzaki
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Okamoto
authors.forename: Hisaaki
authors.initials: H
authors.lastname: Tanaka
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Kuroda