Ligational behaviour of the heterocyclic ligand obtained by coupling of diazotized 2-amino-3-carboxyethyl-4,5-dimethylthiophene with β-naphthol towards some selected lanthanide(III) ions has been studied. Various spectral and physico-chemical techniques have been used to confirm the coordination sites of the ligand (HTAN) and its lanthanide(III) complexes. It has been observed that these ligands coordinate to the metal ions in a neutral tridentate fashion. Thermal stability of metal chelates and structural stability of the chelating agent has been studied by thermal analysis. As lanthanides and azo dyes are reported as good corrosion inhibitors we have examined the corrosion inhibition activities of HTAN and its metal complexes. Also dyeing properties of the azo dye and some of its selected complexes towards cotton fabrics has been evaluated, as the traditional application field of the synthetic azo dyes still remains in the textile industry.

中文翻译：

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1-[（（3-羧乙基-4,5-二甲基噻吩-2-基）偶氮] -2-萘酚的镧系元素（III）配合物的合成，光谱表征，缓蚀研究和染色性能

研究了重氮化的2-氨基-3-羧乙基-4,5-二甲基噻吩与β-萘酚偶合后对某些镧系元素离子的连接作用。各种光谱和物理化学技术已用于确定配体（HTAN）及其镧系元素（III）配合物的配位点。已经观察到这些配体以中性三齿形式配位至金属离子。通过热分析研究了金属螯合物的热稳定性和螯合剂的结构稳定性。由于据报道镧系元素和偶氮染料是良好的腐蚀抑制剂，我们已经研究了HTAN及其金属配合物的腐蚀抑制活性。还评估了偶氮染料及其某些复合物对棉织物的染色性能，