Abstract The effect of film thickness on the structural and optical properties of bisbenzimidazo [2,1-a:2′,1′-a′] anthrax [2,1,9-def:6,5,10-d′e′f′] diisoquinoline-10,21-dione (BI-diisoQ) films was carried out. The morphology of BI-diisoQ film showed a definite shape of a nanorod with a length of around 5 μm and a diameter of approximately 20 nm. Also, X-ray diffraction patterns demonstrated that BI-diisoQ thin films are characterized by a mixture of amorphous and crystalline structure, whereas the phase-nature crystallization of BI-diisoQ film enhanced as the film thickness increased. The investigation of the absorption coefficient of BI-diisoQ films revealed two indirect allowed band gaps energy. The calculated values of nonlinear optical parameters for BI-diisoQ film were observed to be increased with the increase of film thickness. The optical properties of BI-diisoQ nanorod films indicated that these films have appropriate optical properties, and thus it can be recommended as a promised candidate material in superconductors, optoelectronic and photonic applications.

中文翻译：

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用于光学应用的偶氮喹啉衍生物纳米棒有机薄膜的薄膜厚度影响

摘要 薄膜厚度对双苯并咪唑 [2,1-a:2',1'-a'] 炭疽 [2,1,9-def:6,5,10-d'e' 结构和光学性质的影响f']二异喹啉-10,21-二酮（BI-diisoQ）薄膜。BI-diisoQ 薄膜的形态显示出纳米棒的明确形状，长度约为 5 μm，直径约为 20 nm。此外，X 射线衍射图表明 BI-diisoQ 薄膜的特征在于非晶和晶体结构的混合，而 BI-diisoQ 薄膜的相性质结晶随着膜厚度的增加而增强。BI-diisoQ 薄膜吸收系数的研究揭示了两个间接允许的带隙能量。观察到BI-diisoQ薄膜非线性光学参数的计算值随着薄膜厚度的增加而增加。