Abstract
The spectroscopic properties of chlorophylls (MgChl a and H 2Chl a), metallochlorophyll a and b (MgChl a and b, M Ni, Cu and Zn), zinc(II) pyromethylpheophoribide a (ZnPMP a) and zinc(II) chlorin e 6 trimethyl ester (ZnChl e 6 TME) were studied by circular dichroism (CD), magnetic circular dichroism (MCD), X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry (CV). The electronic absorption spectra were assigned in terms of the spectral analysis of CD and MCD. The absorption maximum of the Q y band varied linearly with the electronegativity of the central metal M and the energy level of the macrocyclic π orbitals in MChl a. The semiempirical MO calculation demonstrated that the deviation of H 2Chl a from the general trend is induced by rising of the energy levels of next HOMO and second next HOMO in H 2Chl a. A comparison of the UVVIS and MCD spectral data in zinc(II) chlorophylls revealed that the substituents on the pyrrole β position and the ring V govern the position of the Q and B bands. The spectroscopic behavior was explained on the basis of the energy level of the macrocyclic π orbitals calculated by the conventional MO method.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
