Two pyridine derivatives, 6-(2-chlorophenyl)-2,3-dihydro-1-methyl-3-oxo-2-phenyl-1H-pyrazolo[4,3-b]pyridine-5-carbonitrile (C1) and 6-(4-chlorophenyl)-2,3-dihydro-1-methyl-3-oxo-2-phenyl-1H-pyrazolo[4,3-b] pyridine-5-carbonitrile (C2) are prepared and characterized. Different techniques were applied to confirm their molecular structures. The thermal, structural, optical and diode characteristics of the two pyridine derivatives are reported. X-ray diffraction (XRD) patterns of C1 and C2 in powder form reveal monoclinic polycrystalline nature. The optical functions of C1 and C2 films are calculated from the transmittance and reflectance spectra measured over the spectral range 200–2500 nm. Two indirect allowed optical energy gaps were estimated; 2.55 and 3.13 eV for C1 and 2.7 and 3.27 eV for C2. Thin films of the two compounds were deposited onto p-Si substrates for fabricating heterojunctions. The diode ideality factor and barrier height of both devices were calculated. In addition, Norde's function was used to determine the important parameters of the devices. At relatively high voltage, the conduction mechanism is described by space charge limited current in both devices. The conduction of the device based on C1 and C2 compounds are due to pool–Frenkel and Schottky mechanisms. The data at reverse biasing are also analyzed and estimated. The device based on C1 compound did not give any response to light, while that based on C2 can used as photosensor.

中文翻译：

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吡唑并吡啶衍生物的结构、光学和结特性

两种吡啶衍生物，6-(2-chlorophenyl)-2,3-dihydro-1-methyl-3-oxo-2-phenyl-1H-pyrazolo[4,3-b]pyridine-5-carbonitrile (C1) 和 6 -(4-氯苯基)-2,3-二氢-1-甲基-3-氧代-2-苯基-1H-吡唑并[4,3-b]吡啶-5-甲腈(C2)的制备和表征。应用不同的技术来确认它们的分子结构。报告了两种吡啶衍生物的热、结构、光学和二极管特性。粉末形式的 C1 和 C2 的 X 射线衍射 (XRD) 图案揭示了单斜多晶性质。C1 和 C2 薄膜的光学函数是根据在 200-2500 nm 光谱范围内测量的透射率和反射率光谱计算得出的。估计了两个间接允许的光能隙；C1 为 2.55 和 3.13 eV，C2 为 2.7 和 3.27 eV。两种化合物的薄膜沉积在 p-Si 衬底上，用于制造异质结。计算了两种器件的二极管理想因子和势垒高度。此外，Norde 的功能还用于确定设备的重要参数。在相对较高的电压下，导电机制由两个器件中的空间电荷限制电流来描述。基于 C1 和 C2 化合物的器件的传导是由于池-弗伦克尔和肖特基机制。还分析和估计了反向偏置时的数据。基于C1化合物的器件对光没有任何响应，而基于C2的器件可以用作光传感器。s 函数用于确定设备的重要参数。在相对较高的电压下，导电机制由两个器件中的空间电荷限制电流来描述。基于 C1 和 C2 化合物的器件的传导是由于池-弗伦克尔和肖特基机制。还分析和估计了反向偏置时的数据。基于C1化合物的器件对光没有任何响应，而基于C2的器件可以用作光传感器。s 函数用于确定设备的重要参数。在相对较高的电压下，导电机制由两个器件中的空间电荷限制电流来描述。基于 C1 和 C2 化合物的器件的传导是由于池-弗伦克尔和肖特基机制。还分析和估计了反向偏置时的数据。基于C1化合物的器件对光没有任何响应，而基于C2的器件可以用作光传感器。