ハロゲン化銀における微粒子と大結晶の吸収スペクトルの相違について
1982 年 45 巻 5 号 p. 342-347
詳細
1982 年 45 巻 5 号 p. 342-347
The absorption spectra of fine particles of silver halides in nascent aqueous suspensions have been measured by a stopped-flow technique. The spectra near the absorption edge differed from those of bulk crystals in a way depending on the kind of silver halide: For silver chloride, the absorption coefficient of fine particles was smaller than that of bulk crystals, the shapes of their absorption spectra being almost the same. For silver iodide, the absorption peak of fine particles was located at a shorter wavelength than that of bulk crystals, indicating a large structural difference between them. For silver bromide, the absorption coefficient of fine particles was larger than that of bulk crystals at wavelengths longer than ca. 310 nm, whereas it was smaller at shorter wavelengths. These differences have been interpreted as the effects of exciton sizes as well as of surface strains and disorders in the fine particles.
