Effect Of ? Position?? Position Substituents On The Spectral Properties Of Monolayer Phthalocyanine

Phthalocyanine(Pc),as a macrocyclic aromatic compound with 18-?electron conjugation system,has been applied in the frontier of science and technology in the world due to its unique structure which gives it excellent properties.In this thesis,the physicochemical properties of phthalocyanine derivatives such as atomic charges,molecular orbital energies and compositions,molecular surface electrostatic potential and infrared absorption spectra are discussed at the microscopic level.The quantum chemical calculations of phthalocyanine and its derivatives are carried out on the basis of Density Functional Theory(DFT),and the effects of introducing different numbers or types of substituents at?-positions??-positions on the structure and properties of phthalocyanine and metal phthalocyanine derivatives were analyzed and discussed.The certain change laws were found out,which provide theoretical guidance for the applications of phthalocyanine and its derivatives in the fields of sensors,photosensitizers and catalysts.1.Structural and property studies of octaethylthio-substituted phthalocyanines at the?-position.Using a combined experimental and theoretical research method.Density functional theory(DFT)was used to optimized the structure of?-position octasubstituted phthalocyanine with ethylthio group,?-(SC₂H₅)₈-H₂Pc and?-position octasubstituted iron(II)phthalocyanine with ethylthio group,?-(SC₂H₅)₈-Fe Pc at B3LYP/6-31G(d)level,and the infrared absorption spectra were simulated.Through the study of the geometric parameters,molecular orbital energies,molecular surface electrostatic potential and infrared absorption spectra of the molecules,we discussed the effects of central metal and introducing substituents at?-positions on the structure and spectroscopic properties of phthalocyanine.Our research provides theoretical reference for the application of these phthalocyanine derivatives in the field of chemical sensors.2.Structural and property studies of Ethoxy-Morpholine substituted phthalocyanines.Quantum chemical calculations have been performed on a series of phthalocyanine derivatives of?-site substituted metal phthalocyanines at the B3LYP/6-31G(d)level using the method of Density Functional Theory.The substituents of this series of phthalocyanine derivatives are Ethoxy-Morpholine,the central metals of phthalocyanine macrocycles are zinc and magnesium:?-(Et O-ML)₂-Zn Pc??-(Et O-ML)₈-Zn Pc??-(Et O-ML)₈-Mg Pc.In order to confirm and predict their properties,the geometrical parameters,charge density,molecular orbital energy,and molecular surface electrostatic potential of these compounds have been theoretically calculated and discussed in detail.The corresponding theoretical calculations can help to understand the intrinsic mechanism of this series of phthalocyanine compounds involved in chemical reactions and provide theoretical references concerning the application of phthalocyanines as photosensitizers in photodynamic therapy.3.Structural and property studies of electron-donating groups or electron-absorbing groups substituted phthalocyanines.Theoretical calculation and simulation of?-(NH₂)₄-Al Cl Pc??-(OH)₄-Al Cl Pc??-(NO₂)₄-Al Cl Pc??-(COOH)₄-Al Cl Pc at the B3LYP/6-31G(d)level using the method of Density Functional Theory.The effects of different types of substituents on the geometrical parameters,molecular _orbital energies,molecular surface electrostatic potential,infrared absorption spectra and other properties of phthalocyanines are discussed at the microscopic level of molecules.To provide a microscopic level reference for the physical and chemical properties of such phthalocyanine derivatives and to provide theoretical support for subsequent applications in the field of catalysts.