Electronic spectra of organic molecules and their interpretation—V : Effect of terminal groups containing multiple bonds on the K-bands of conjugated systems

摘要: Abstract The investigation of the effect terminal groups absorbing (conjugated) systems on corresponding K-bands is extended to containing multiple bonds. A consistent theoretical interpretation all observations given based consideration electronic perturbations in excited state (due Heisenberg resonance) and view that organic molecules are built up localised bonds involve inductive electron-shifts only. empirical comparative analysis experimental data shows conclusively that, contrast conclusions arrived at by mathematical methods, 2000 A, not 1800 band system benzene corresponds an (approximate) symmetry 1E1μ (involving allowed transition characteristic for K-bands).