A Vector-based Representation Of The Chemical Bond For The Normal Modes Of Benzene And The Excited States Of Fulvene

In this thesis,introduce a vector-based representation of the chemical bond methods.And using the"Quantum Theory of Atoms in The molecules"?QTAIM?and stress tensors are used to analyze the characters of their crossing points.These data are performed with Gaussian 09 packets and topological analysis of the molecules used for the total electron charge density distribution??r?with AIMALL.Main content Contains 5 relatively independent chapters,more detailscan be seen as following:In chapter 1,we briefly recapitulate the basic concepts of QTAIM and stress tensor,in order to get a good understanding for most reader.In the chapter 2,using QTAIM and new QTAIM-based vector representation of the chemical bond to distinguish between the S₀ and S₁electronic states of fulveneIn the chapter 3,using QTAIM and a new QTAIM-based vector representation of the chemical bond to gain new insights into the subtle details of the four infrared?IR?active normal modes of vibration of benzene.In the chapter 4,a visualization of the 3-D morphology of all the C-C and C-H bonds for the four infra-red?IR?active normal modes of benzene using the complete bond-path framework set={p,q,r}a vector-based interpretation of the chemical bond within the QTAIM framework.In the chapter 5,based on the present results,as well as previous reported references and further work are described.