ORGANIC PHOTOCHROMIC COMPOUND

提出了几种具有不同转化机理的有机光致变色化合物，用于研究它们的光学性质和固体形式的光反应：呋喃甲酰(电环化)、偶氮苯(E-Z异构化)和N-水杨叉基苯胺(氢转移)。找到了晶体生长的条件。在1-30 eV的宽能量范围内测量了单晶的偏振反射光谱，并根据K-K关系将结果转换为吸收光谱。通过在晶体中形成Frenkel激子，使光谱向低能方向移动，单分子能图(pi-pi*跃迁)很好地解释了光谱的变化，成功地利用光致变色化合物的单晶实现了材料的光调控。通过大吸收系数的光的照射，在黄腐酸晶体表面生长了一层异构体薄膜。薄膜只对平行于晶体b轴的偏振光有吸收，表明薄膜具有良好的取向。光在晶体中的光学掺杂也是通过照射吸收系数较小的光来实现的。光生材料的吸收带随薄膜产生的材料量的增加而蓝移，而密度与表面膜相比稀薄的光掺杂材料的吸收带则发生红移。合成了不同大小的烷基取代基呋喃类化合物，考察了它们的显色量子产率、漂白量子产率和吸收光谱的变化。

Organic photochromic compounds which have different kinds of transformation mechanism are brought up for the studies of optical properties and photoreaction in solid form : furylfulgide (electrocyclization), azobenzene (E-Z isomerization and N-salicylideneaniline (hydrogen transfer). The conditions of crystal growth are found. Polarized reflection spectra of the single crystals are measured for wide energy range from 1 to 30 eV,and results are transformed to absorption spectra by the K-K relation. The spectra are well understood by the energy diagram of single molecule (pi-pi* transition), though the spectra are shift to the lower energy a little by forming Frenkel excitons in the crystal.A try of material control by light, using single crystals of the photochromic compounds is done successfully. A film of the isomer on the fulgide crystal surface is grown by irradiation of the light with large absorption coefficient. The film has absorption only for the light polarized parallel to the b axis of the crystal, showing that the films are well oriented. Optical doping in to the crystal by light is also done by irradiation of the light with small absorption coefficient. An absorption band by the photoproduced material shows blue shift with increasing the amounts of the produced material for the film, on the other hand, red shift for the photodoped materials which are dilute in density compared with the surface film. All the photoproduced material on the surface or inside of the crystal was able to be erased by the irradiation of the visible light.Furylfulgides with different sizes of alkyl substitituents were synthesized and their photochromic properties of the quantum yield of coloration, bleaching quantum yeild and the change of the absorption spectra were examined.