Study on Thermodynamics of Three Kinds of Benzindocarbocyanine Dyes in Aqueous Methanol Solution

Bulletin of the Korean chemical society

Fang Li Fan¹  Zhen Yi Wen¹  Gao Hong Zhai¹  Wei Huang¹  Lan Ying Wang¹  You Ni Tao¹  Yi Le Fu¹  Ji Quan Liu¹ 

关键词: Benzindocarbocyanine dye;    Thermodynamic property;    Aggregation state;   

DOI  :  

学科分类：化学（综合）

来源: Korean Chemical Society

【 摘 要 】

Aggregation behavior of three kinds of benzindocarbocyanine dyes in aqueous methanol solution was studied by UV-Vis absorption spectrum. The results indicated that the three dyes all existed monomer-dimer equilibrium in aqueous methanol solution (concentration range 10^-5 to 10^-6 M) at 25.0~41.0�? for Dye 1, 28.0~49.0�? for Dye 2 and 26.0~47.0�? for Dye 3. The fundamental property of the three dyes as the dimeric association constant KD, the dimeric free energy �?G_D, the dimeric entropy �?S_D, and the dimeric enthalpy �?H_D were determined. The �?HD of three dyes: Dye 1, Dye 2 and Dye 3 was -42.5, -15.1 and -18.9 kJ/mol, respectively. The experimental observations were the subject of a theoretical study including the ground-state geometries which were fully optimized using DFT at B3LYP/6-31G level. The effect of dye molecule structure on �?H_D was discussed by theoretical calculations.

【 授权许可】

Unknown