S1 Supporting Information for Two-photon absorption properties of heterafluorenes and spirobiheterafluorenes bearing aminostyryl arms Tomohiro Agou, † Md. Delwar Hossain, † Takayuki Kawashima,* ,† Kenji Kamada, ‡ and Koji Ohta ‡ † Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan ‡ Photonics Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), AIST Kansai Center, Ikeda, Osaka 563-8577, Japan takayuki@chem.s.u-tokyo.ac.jp Table of Contents Experimental details S2 Fig. S1. UV-vis spectra of 3 and 4 in dichloromethane S5 Fig. S2. Fluorescence spectra of 3 and 4 in dichloromethane S5 Fig. S3. UV-vis spectra of 3 and 4 in toluene S6 Fig. S4. Fluorescence spectra of 3 and 4 in toluene S6 Fig. S5. UV-vis spectra of 3 and 4 in acetone S7 Two-photon absorption measurement and analysis S8 References S10 Supplementary Material (ESI) for Chemical Communications This journal is (c) The Royal Society of Chemistry 2009