title: Highly Oriented J-Aggregates of Nitroazo Dye and Its Surface-Induced Chromism.
abstract: Highly oriented J-aggregates of a nitroazo dye were obtained in solid thin films on aligned poly(tetrafluoroethylene) surfaces. During film deposition on a friction-transferred poly(tetrafluoroethylene) layer, a sharp peak grew in the polarized absorption spectra around 613 nm, which was red-shifted 117 nm from the peak in dilute dichloromethane solution. The peak showed remarkable optical anisotropy: dichroic ratios D of up to 22 were observed, and the intrinsic D value should substantially exceed this value. These results indicate that the peak is attributable to highly oriented J-aggregates. On glass, however, H-like aggregates grew, exhibiting an absorption peak at 410 nm. Hence, the substrate surface induced the remarkable chromism observed as a 203 nm red shift.
authors.affiliation: Department of Chemistry and Biochemistry, Fukushima College, National Institute of Technology , 30 Aza-Nagao, Tairakamiarakawa, Iwaki, Fukushima 970-8034, Japan.|ASET Sumitomo Chemical laboratory, Tsukuba Research Laboratory, Sumitomo Chemical Co. Ltd., 6 Kitahara, Tsukuba, Ibaraki 300-3294, Japan.|RIKEN Advanced Science Institute , 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.|Department of Environment and Natural Sciences, Graduate School of Environment and Information Sciences, Yokohama National University , 79-7 Tokiwadai, Hodogaya-ku, Yokohama, Kanagawa 240-8501, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Tanaka
authors.affiliation: ASET Sumitomo Chemical laboratory, Tsukuba Research Laboratory, Sumitomo Chemical Co. Ltd., 6 Kitahara, Tsukuba, Ibaraki 300-3294, Japan.
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Ishitobi
authors.affiliation: RIKEN Advanced Science Institute , 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Aoyama
authors.affiliation: Department of Environment and Natural Sciences, Graduate School of Environment and Information Sciences, Yokohama National University , 79-7 Tokiwadai, Hodogaya-ku, Yokohama, Kanagawa 240-8501, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Matsumoto