Pyridine-3-carbohydrazide (NIH) crystal is grown by slow evaporation solution growth technique and the single crystal X-ray diffraction experiment confirms cell parameters and space group. The FT-IR and FT-Raman studies are used to identify the functional groups in the compound Nicotinohydrazide. The thermal studies are conducted using thermogravimetric analysis and differential thermal analysis, the UV–Visible transmission spectrum of NIH is recorded within the range of 400–800nm. Besides, in order to know the optical properties of the material at molecular level, density functional theory (DFT) has been employed using B3LYP method at 6-311+G (d,p). The electric dipole moment and first-order hyperpolarizability are calculated and found to be high. The second-order NLO studies for NIH crystal are done and it is compared with KDP.

中文翻译：

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新型非线性光学材料烟酰肼的理论与实验研究

吡啶-3-碳酰肼(NIH)晶体采用慢蒸发溶液生长技术生长，单晶X射线衍射实验证实了晶胞参数和空间群。FT-IR 和 FT-Raman 研究用于鉴定化合物 Nicotinohydrazide 中的官能团。热学研究是使用热重分析和差热分析进行的，NIH 的紫外-可见透射光谱记录在 400-800 范围内纳米。此外，为了在分子水平上了解材料的光学性质，已采用密度泛函理论 (DFT) 使用 B3LYP 方法在 6-311+G(d,p)。计算了电偶极矩和一阶超极化率，发现它很高。完成了NIH晶体的二阶NLO研究，并与KDP进行了比较。