The phase diagram representing solid–liquid equilibrium of entire range of composition and thermodynamic studies of two binary organic systems of 4-dimethylaminobenzaldehyde (DMAB) with two NLO active compounds, p-aminoacetanilide (PAA) and p-nitroaniline (PNA), have been studied by solid state synthetic route. Both systems are independently forming a new entity called intermolecular complex (IMC) and two eutectics on either side of intermolecular complexes. The various thermodynamic parameters such as heat of mixing, entropy of fusion, roughness parameter, interfacial energy and excess thermodynamic functions of IMCs and eutectics were calculated using the heat of fusion values. The TGA and DTA studies were performed to understand the physico-chemical, thermal behavior and unique identity of newly synthesized organic complexes, 4-(dimethylamino)benzylidene-4-acetamideaniline (DMABPAA) and 4-(dimethylamino)benzylidene-4-nitroaniline (DMABPNA), and their respective enthalpy of fusion values were found to be 30.01 and 37.26 kJ mol^− 1. The higher melting point of both the novel complexes than their parent’s compounds reveal the strong molecular interaction between parent components to yield the complex. The FTIR spectral analysis predicts the disappearance of aldehyde peaks of DMAB and NH₂ peaks of PAA and PNA while the appearance of entirely new peaks than that of parent’s compounds are the supportive for the formation of new molecular entities. These findings are further supported by FTNMR spectrum studies by observation of disappearance of proton peak of aldehyde of DMAB and amine peaks of PAA and PNA rather formation of new imine proton peak or peaks were observed. The appearance of new peaks in Powder XRD of complexes than those of parent components is further indicative for the formation of complexes. The absorption spectrum of DMABPAA and DMABPNA showed intra-molecular charge-transfer (ICT) excited state absorption at 258 and 241 nm, respectively. Both the IMCs, DMABPAA and DMABPNA, show strong fluorescence with quantum yield 0.66 and 0.93, respectively, in methanol solution.

中文翻译：

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新型配合物的合成，光谱表征，热和光学研究：4-（二甲基氨基）亚苄基-4-乙酰胺苯胺和4-（二甲基氨基）亚苄基-4-硝基苯胺。

相图代表了整个组成范围的固液平衡，并且对两个二甲基有机物的4-二甲基氨基苯甲醛（DMAB）与两种NLO活性化合物对氨基乙酰苯胺（PAA）和对硝基苯胺（PNA）进行了热力学研究。通过固态合成路线研究。这两个系统独立地形成了一个新的实体，称为分子间复合物（IMC），并且在分子间复合物的任一侧形成了两个共晶。使用熔化热值计算了各种热力学参数，例如混合热，熔化熵，粗糙度参数，界面能以及IMC和共晶的过剩热力学函数。进行了TGA和DTA研究，以了解新合成的有机配合物的理化，热行为和独特性，^{- 1}。两种新型配合物的熔点均高于其母体化合物的熔点，揭示了母体组分之间的强分子相互作用，从而产生了配合物。FTIR光谱分析预测DMAB和NH ₂的醛峰消失PAA和PNA的峰出现，而比母体化合物出现的全新峰则支持形成新的分子实体。FTNMR光谱研究通过观察DMAB的醛的质子峰的消失以及PAA和PNA的胺峰的消失而观察到新的亚胺质子峰的形成而进一步支持了这些发现。与母体组分相比，复合物粉末XRD中出现新的峰进一步指示了复合物的形成。DMABPAA和DMABPNA的吸收光谱分别显示了在258和241 nm处的分子内电荷转移（ICT）激发态吸收。IMC DMABPAA和DMABPNA在甲醇溶液中均显示强荧光，量子产率分别为0.66和0.93。