Ionization of chlorophyll-c2 in liquid methanol

• Published in: Chemical physics letters 2012-09, Vol.546, p.67-73
• Main Authors: Jaramillo, Paula, Coutinho, Kaline, Cabral, Benedito J. Costa, Canuto, Sylvio
• Format: Article
• Language: English
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/j.cplett.2012.07.040

[Display omitted] ► We present results for the first ionization of chlorophyll-c2 in liquid methanol. ► Ionization energies for clusters of chlorophyll-c2 with methanol are presented. ► The ionization energy of chlorophyll-c2 in liquid methanol is red-shifted by 0.5eV. ► The ionization threshold for chlorophyll-c2 in liquid methanol is below 6eV. ► The electronic density of states of chlorophyll-c2 in liquid methanol is reported. The ionization of chlorophyll-c2 in liquid methanol was investigated by a sequential quantum mechanical/Monte Carlo approach. Focus was placed on the determination of the first ionization energy of chlorophyll-c2. The results show that the first vertical ionization energy (IE) is red-shifted by 0.47±0.24eV relative to the gas-phase value. The red-shift of the chlorophyll-c2 IE in the liquid phase can be explained by Mg⋯OH hydrogen bonding and long-ranged electrostatic interactions in solution. The ionization threshold for chlorophyll-c2 in liquid methanol is close to 6eV.