Department of Chemistry, Materials and Chemical Engineering "G. Natta", Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milano, Italy.
CNR-SCITEC Istituto di Scienze e Tecnologie Chimiche, Via Alfonso Corti 12, 20133 Milano, Italy.
Molecules. 2020 Mar 25;25(7):1495. doi: 10.3390/molecules25071495.
UV-VIS spectroscopy analysis of six mixtures containing choline chloride or triphenylmethylphosphonium bromide as the hydrogen bond acceptor (HBA) and different hydrogen bond donors (HBDs, nickel sulphate, imidazole, d-glucose, ethylene glycol, and glycerol) allowed to determine the indirect and direct band-gap energies through the Tauc plot method. Band-gap energies were compared to those relative to known choline chloride-containing deep band-gap systems. The measurements reported here confirmed the tendency of alcohols or Lewis acids to increment band-gap energy when employed as HBDs. Indirect band-gap energy of 3.74 eV was obtained in the case of the triphenylmethylphosphonium bromide/ethylene glycol system, which represents the smallest transition energy ever reported to date for such kind of systems.
使用 UV-VIS 光谱分析六种混合物，其中包含氯化胆碱或三苯甲基膦溴化物作为氢键受体（HBA）和不同的氢键供体（HBD，硫酸镍、咪唑、D-葡萄糖、乙二醇和甘油），通过 Tauc 图法确定间接和直接带隙能。将带隙能与已知的含氯化胆碱的深带隙系统进行比较。这里报道的测量结果证实了醇或路易斯酸作为 HBD 使用时增加带隙能的趋势。在三苯甲基膦溴化物/乙二醇体系中获得了 3.74eV 的间接带隙能，这是迄今为止此类体系报道的最小跃迁能。
