光誘起不安定ラジカル種のX線結晶解析による観測
2001 年 43 巻 2 号 p. 164-168
詳細
2001 年 43 巻 2 号 p. 164-168
The structures of light-induced unstable species of photo/thermo/piezochromic compounds, hexaarylbiimidazolyl derivatives (o-Cl-HABI and HABI), cryotrapped in the single crystals were characterized by in situ X-ray crystallography. Photolysis of a crystal of o-Cl-HABI at low temperatures produced radical pairs with retaining the crystallinity. On the other hand, a pair of HABI was transformed to a complex composed of two lophyl radicals and a piezodimer on irradiation at low temperatures. The piezodimer, the existence of which has been assumed spectroscopically as an unstable isomer, was produced via molecular swapping of two photoinduced lophyl radicals with drastic conformational changes. These solid-state photoreactions were confirmed by spectroscopic methods and theoretical calculations as well.
