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Unraveling the Electronic Structure, Spin States, Optical and Vibrational Spectra of Malaria Pigment
Author(s) -
Ali Md. Ehesan,
Oppeneer Peter M.
Publication year - 2015
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201406208
Subject(s) - hemozoin , density functional theory , electronic structure , chemistry , antiferromagnetism , singlet state , absorption spectroscopy , spectral line , ground state , spectroscopy , computational chemistry , heme , atomic physics , condensed matter physics , optics , physics , excited state , organic chemistry , quantum mechanics , astronomy , enzyme
A detailed knowledge of the electronic structure and magnetic and optical properties of hemozoin, the malaria pigment, is essential for the design of effective antimalarial drugs and malarial diagnosis. By employing state‐of‐the‐art electronic structure calculations, we have performed an in‐depth investigation of the malaria pigment. Specifically, molecular bond lengths and spin states of the two Fe III heme centers and their exchange interaction, the UV/Vis absorption spectrum, and the IR vibrational spectra were calculated and compared with available experimental data. Our density functional theory (DFT)‐based calculations predict a singlet ground spin state that stems from an S=5/2 spin state on each of the Fe heme centers with a very weak antiferromagnetic exchange interaction between them. Our theoretical UV/Vis and IR spectra provide explanations for various spectroscopic studies of hemozoin and β‐hematin (a synthetic analogue of hemozoin). A good comparison of calculated and measured properties demonstrates the convincing unveiling of the electronic structure of the malaria pigment. Based on the predicted vibrational spectra, we propose a unique spectral band from the nuclear resonance vibrational spectroscopy (NRVS) results that could be used as a key fingerprint for malarial detection.