ORGANIC PHOTOCHROMIC COMPOUND

本文提出了具有不同转化机理的有机光致变色化合物：呋喃酰脲（电环化）、偶氮苯（E-Z异构化）和n -水杨基苯胺（氢转移）。发现了晶体生长的条件。测量了单晶在1 ~ 30 eV宽能量范围内的偏振反射光谱，并通过K-K关系将结果转化为吸收光谱。单分子的能量图（pi-pi*跃迁）可以很好地理解光谱，但由于晶体中形成了Frenkel激子，光谱会向较低的能量方向偏移。利用光致变色化合物的单晶，成功地进行了光控制材料的尝试。利用吸收系数大的光照射，在富勒德晶体表面生长了一层异构体膜。薄膜仅对平行于晶体b轴偏振光有吸收，表明薄膜取向良好。光在晶体中的光学掺杂也是通过小吸收系数光的辐照来实现的。光产生的材料的吸收带随着所产生的材料的量的增加而出现蓝移，另一方面，与表面膜相比密度被稀释的光掺杂材料的吸收带出现红移。在可见光的照射下，晶体表面或内部的所有光产生的物质都能被擦除。合成了不同尺寸的烷基取代基呋喃呋喃酯，考察了它们的光致变色性能，着色量子产率、漂白量子产率以及吸收光谱的变化。

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.