[18a-G205-1~8] 12.1 Fabrications and Structure Controls

[18a-G205-4] Crystal Polymorphs and Crystal-to-Crystal Thermal Phase Transition of Alkyl-substituted Phthalocyanine

〇Masashi Ohmori¹, Chika Nakano¹, Makoto Yoneya², Akihiko Fujii¹, Masanori Ozaki¹ (1.Osaka Univ., 2.AIST-Tsukuba)

Keywords:crystal polymorph, phthalocyanine, phase transition

Two types of crystal polymorphs were fabricated by two types of recrystallization methods, and selective crystal growth of the crystal polymorphs was clarified. The irreversible crystal-to-crystal phase transition was observed by the differential scanning calorimetry and X-ray structure analysis, and the stability of the crystal polymorphs were discussed by the Gibbs free energy and disorder of the alkyl-substituents. One of the crystal polymorphs exhibited high carrier mobility by density functional theory calculation, and importance of the selective crystal growth of the crystal polymorphs were indicated.