[Study on the auxochrome of the electronic spectrum of organic compounds and its effect mechanism (II)].
The interaction between the p orbit of the auxochrome, the maximum bonding orbit (pi) and the minimum antibonding orbit (pi*) of the chromophore forms three new molecular orbit, among which the antibonding orbit (pi*') has the highest energy that is higher than those of the original pi*. The maximum occupied orbit (pi') will have energy lower or higher than those of pi according to different auxochrome and chromophore, and the energy of n orbit will remain steady, because the n orbit of the original chromophore is perpendicular to the p orbit of the auxochrome and the interaction is negligeable. As a result, the absorption wavelength of transition n-->pi* will shift towards higher photon energy, but for transition pi-->pi*, the absorption wavelength will shift towards either lower or higher photon energy, depending on the species of auxochrome and chromophore.
Wang
Ying
Y
Analysis Center Tianjin University, Tianjin 300072, China.
Jiang
Long-ping
LP
Li
Run-qing
RQ
Kuang
Qing
Q
Zhou
Wei-yi
WY
D055598:Chemical Phenomena; D002627:Chemistry, Physical; D004583:Electrons; D008958:Models, Molecular; D009930:Organic Chemicals / Q000737:chemistry*; D010777:Photochemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D013053:Spectrophotometry / Q000379:methods; D013056:Spectrophotometry, Ultraviolet / Q000379:methods*
D009930:Organic Chemicals; D011092:Polyethylene Glycols; C018557:glycofurol