Abstract Single crystals of a novel organic nonlinear optical (NLO) material-guanidinium hippurate monohydrate (GuHM) -are grown using slow evaporation solution growth technique. GuHM is an anion-cation system to which water molecules are attached by hydrogen bonding. The lattice parameters and crystalline purity of the crystal have been measured using single-crystal and powder X-ray diffraction (XRD) methods. Quantum chemical calculations using density functional theory (DFT) have been employed to calculate the vibrational modes and the first and second hyperpolarizabilities. Thermogravimetric (TG) and differential thermal (DT) analyses were carried out to characterize the thermal behaviour of the grown crystals. The role of intramolecular charge transfer and hydrogen bonds in making the molecule NLO-active are interpreted on the basis of the hyperpolarizability values. Along with DFT calculations, the natural bond orbital (NBO), the Atoms In Molecules (AIM), and the Hirshfeld surface imply the presence of a strong intra- and intermolecular N–H….O and O–H….O hydrogen bonding interactions between the charged species of GUHM crystal. The third-order optical nonlinearity of the crystal was studied using open-aperture Z-scan technique. From the experimental and theoretical data, it is concluded that GuHM is a potential NLO material.

中文翻译：

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马尿酸胍一水合物单晶的合成、生长和表征：一种新型三阶非线性光学材料

摘要 使用缓慢蒸发溶液生长技术生长了一种新型有机非线性光学 (NLO) 材料 - 马尿酸胍 (GuHM) 的单晶。GuHM 是一种阴离子-阳离子系统，水分子通过氢键连接到该系统上。使用单晶和粉末 X 射线衍射 (XRD) 方法测量了晶体的晶格参数和晶体纯度。使用密度泛函理论 (DFT) 的量子化学计算已被用于计算振动模式以及第一和第二超极化率。进行热重 (TG) 和差热 (DT) 分析以表征生长晶体的热行为。分子内电荷转移和氢键在使分子 NLO 具有活性方面的作用是根据超极化值来解释的。随着 DFT 计算，自然键轨道 (NBO)、分子中的原子 (AIM) 和 Hirshfeld 表面暗示存在强大的分子内和分子间 N–H….O 和 O–H….O 氢键GUHM 晶体带电物质之间的相互作用。使用开放孔径 Z 扫描技术研究了晶体的三阶光学非线性。从实验和理论数据可以得出结论，GuHM 是一种潜在的 NLO 材料。GUHM 晶体带电物质之间的 O 氢键相互作用。使用开放孔径 Z 扫描技术研究了晶体的三阶光学非线性。从实验和理论数据可以得出结论，GuHM 是一种潜在的 NLO 材料。GUHM 晶体带电物质之间的 O 氢键相互作用。使用开放孔径 Z 扫描技术研究了晶体的三阶光学非线性。从实验和理论数据可以得出结论，GuHM 是一种潜在的 NLO 材料。