title: Near-Infrared Photoluminescence Properties of Endohedral Mono- and Dithulium Metallofullerenes.
abstract: The optical properties of endohedral metallofullerene molecules can be tuned by changing the fullerene size as well as the number of metal atoms inside the fullerene cages. In this work we have synthesized and isolated a series of mono- and dithulium metallofullerenes, including Tm@C82 (isomers I, II, III, IV), Tm@C88 (I-IV), Tm2@C82 (I-III), and (Tm2C2)@C82 (I-III). Near-infrared photoluminescence is observed from the thulium metallofullerenes. By changing the number of Tm ion in the fullerene cage, we have found that one can vary and tune the photoluminescence from 1200 to 1300-2000 nm observed for Tm(2+) (4f(13)) in Tm@C88 and Tm(3+) (4f(12)) in (Tm2C2)@C82, respectively. The photoluminescence intensity depends sensitively on the fullerene cages. (Tm2C2)@C82 (III) exhibits the highest photoluminescence intensity among the three structural isomers because of its large HOMO-LUMO energy gap.
authors.affiliation: Department of Chemistry and Institute for Advanced Research, Nagoya University , Nagoya 464-8602, Japan.
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Chemistry and Institute for Advanced Research, Nagoya University , Nagoya 464-8602, Japan.
authors.forename: Noriko
authors.initials: N
authors.lastname: Izumi
authors.affiliation: Department of Chemistry and Institute for Advanced Research, Nagoya University , Nagoya 464-8602, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Nakanishi
authors.affiliation: Department of Applied Physics, Nagoya University , Nagoya 464-8603, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Koyama
authors.affiliation: Department of Chemistry and Institute for Advanced Research, Nagoya University , Nagoya 464-8602, Japan.
authors.forename: Toshiki
authors.initials: T
authors.lastname: Sugai
authors.affiliation: Nanotube Research Center, National Institute of Advanced Industrial Science and Technology (AIST) , Tsukuba 305-8565, Japan.
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Tange
authors.affiliation: Nanotube Research Center, National Institute of Advanced Industrial Science and Technology (AIST) , Tsukuba 305-8565, Japan.
authors.forename: Toshiya
authors.initials: T
authors.lastname: Okazaki
authors.affiliation: Department of Chemistry and Institute for Advanced Research, Nagoya University , Nagoya 464-8602, Japan.
authors.forename: Hisanori
authors.initials: H
authors.lastname: Shinohara
keywords: fullerene; lanthanide; metallofullerene; photoluminescence; thulium