Controlling of color in organic compound by means of electronic theory

小川禅, 石井知彦, 劔持雅弘, 渡辺洋平, 坂根弦太

有機化合物, 電子スペクトル
Many kinds of pigment materials have been investigated and developed mainly by an inorganic materials based on the metals or the metal complexes, whereas a colorless is one of the most famous characters in the organic materials. However, rising of the prices of the rare metal and rare earth in recent years is one of the most serious problems in the world. Therefore in this study, our purpose is to create a new pigment material based on an organic compounds, which can be synthesized at a lower price than that of the inorganic based material. In general, the color can be observed as a result of the absorption caused by the electron excitation among the electronic level structure. Therefor, we investigate the electronic structure of the organic compounds in order to control and to expect the color of the organic materials by means of the DV-Xα molecular orbital approach. In this study, the changing of the electronic structure can be compared by changing the molecular sizes, atoms, and the shape of the π-conjugated molecular orientation, such as,
1. changing in the number of a carbon atoms in a ring, 
2. changing in the number of benzene rings, 
3. substituting the carbon atom for the nitrogen or oxygen atoms. 
We realized that the energy gap can be controlled freely by changing the molecular structure according to above three ways.

Bulletin of the Society for Discrete Variational Xα

The Society for Discrete Variational Xα

23

1&2

197

204