摘要
Abstract
To explore the influence of molecular structure of dispersed dye on its light absorption perform-ance,based on the principle of quantum energy level light absorption,taking the monodiazo series structure dis-persed dye as an example,Gaussian quantum chemical calculation software was applied for structural optimization and excited state calculation research,and the correlation between molecular structure energy levels and their col-oring performance was analyzed.Confab was adopted to generate initial conformations for each structure and batch optimization under GFN2-xTB was conducted.By using quantum chemical density functional theory optimization,the lowest energy dye molecule conformation,free energy thermal correction amount,single point energy of each conformation under M06-2X/def2-TZVPP conditions,free energy at 298.15 K temperature and Boltzmann dis-tribution ratio were obtained.A conformation with a not less than 5%Boltzmann distribution ratio was selected for excited state calculation,and the UV visible absorption spectrum data and maximum absorption wavelength of the dye were acquired.The analysis of the molecular structure conformation,molecular orbitals,excited state orbital transitions and contribution rates,absorption spectra and maximum absorption wavelength of the dispersed dyes showed that the type,number and distribution positions of substituents such as chlorine and bromine had a signif-icant influence on the stability and light absorption performance of dye molecule conformation,and ultimately af-fected the coloring performance of the dispersed dyes.The distribution and energy gap of HOMO and LUMO or-bitals directly affected the maximum absorption wavelength.关键词
分散染料/量子化学/光吸收性能/密度泛函理论/最大吸收波长Key words
dispersed dyes/quantum chemistry/light absorption performance/density functional theory/maximum absorption wavelength分类
轻工纺织
