ORGANIC CHEMISTRY Chapter 13 不π(LUMO 平73*(LUMO excitation excitation 丌2(HOMO) 丌(HOMO) CH2-CH2 CH2=CH一CH=CH max 171 nm 217nm Department of Chemistry, Xiamen UniversityORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 13 excitation excitation π*(LUMO) π3*(LUMO) π(HOMO) π1 π2(HOMO) π4* CH2 CH2 CH2 CH CH CH2 λmax 171 nm 217 nm