Acta Phys. -Chim. Sin. ›› 1996, Vol. 12 ›› Issue (03): 202-207.doi: 10.3866/PKU.WHXB19960303

• ARTICLE • Previous Articles     Next Articles

Effects of Protonation and Deprotonation on Phthalocyanine's Spectra

Liu Jian-Bo, Zhao Yu, Zhao Fu-Qun, Zhang Fu-Shi, Tang Ying-Wu, Song Xin-qi, Zhou Fu-Tian   

  1. Department of Chemistry,Tsinghua University,Beijing 100084|Department of Applied Biology and Chemical Technology,Hong Kong Polytechnic University,Hong Kong
  • Received:1995-05-16 Revised:1995-07-06 Published:1996-03-15
  • Contact: Liu Jian-Bo


The absorption and emission properties of H2Pc(OiPr)4 were studied as a function of protonation and deprotonation. Stepwise protonation using TFA yielded [H2Pc(OiPr)4•H+]+ and [H2Pc(OiPr)4•2H+]2+. [H2Pc(OiPr)4•4H+]4+ can be formed in concentrated sulfuric acid. Additionally, the NaOH/EtOH can deprotonate H2Pc(OiPr)4 to [Pc(OiPr)4]2-, the acid-dissociation of the two pyrrolic -NH occurred synchronous. Manifest bathochromic shifts of the Q band absorption for each bound proton indicated the basicity of phthalocyanine in the excided state is stronger than that in the ground state. In order to explain the experimental phenomena, the effects of protonation and deprotonation on MOs were proposed.

Key words: Phthalocyanine, Protonation, Deprotonation