Department of Physic, Bharathiar University, Coimbatore, India.
Department of Medical Physics, Bharathiar University, Coimbatore, India.
J Mol Model. 2019 Dec 13;26(1):6. doi: 10.1007/s00894-019-4205-2.
In the present investigation, we have employed heme as a material for absorbing haloarenes due to its unique structural property, abundant availability, non-toxic nature and its dynamic nature in absorbing oxygen molecule. Haloarenes are toxic gases that are released into atmosphere as an aftermath of various refrigerants. Using first principle study, the absorption of haloarenes on heme molecule was systematically investigated. Fluorine, Chlorine, Bromine and Iodine substituted Haloarenes were allowed to interact with heme molecule with metal ion at +2, +3 and + 4 oxidation states of both low and high spin states. The TD-DFT analysis shows that the heme is a better absorbent at +3 and + 4 oxidation states of Fe ion at low spin state. Among the haloarenes, the interaction energy between IHA and Fe ion at +4 state is maximum with -1.877 eV. The HOMO-LUMO band gap decreases with increase in oxidation state and the orbital delocalization is maximum for high oxidation state. The delocalization of these electronic orbitals shows the active interaction between the heme molecule and haloarene which was confirmed by the DOS plot and the LP to LP* transition in NBO analysis. The absorbing nature of heme was further extended to hexahaloarenes, where heme still stand as a strong absorbing candidate for these toxic gases. The detailed study of the interaction between heme and haloarenes showed that heme at low spin state and with both +3 and + 4 oxidation states can be employed as an absorbent for Haloarenes. Graphical abstract.
在本研究中，我们采用血红素作为吸收卤代芳烃的材料，这是由于其独特的结构特性、丰富的可用性、无毒性质以及其动态吸收氧气分子的性质。卤代芳烃是有毒气体，作为各种制冷剂的后果释放到大气中。使用第一性原理研究，系统地研究了卤代芳烃在血红素分子上的吸收。允许氟、氯、溴和碘取代的卤代芳烃与血红素分子与金属离子相互作用，金属离子的氧化态为+2、+3 和+4，自旋态为低自旋和高自旋。TD-DFT 分析表明，在低自旋态下，Fe 离子的+3 和+4 氧化态的血红素有更好的吸收能力。在卤代芳烃中，IHA 与+4 态 Fe 离子之间的相互作用能最大，为-1.877 eV。HOMO-LUMO 带隙随氧化态的增加而减小，高氧化态下轨道离域最大。这些电子轨道的离域表明血红素分子与卤代芳烃之间存在活跃的相互作用，这通过 DOS 图和 NBO 分析中的 LP 到 LP*跃迁得到了证实。血红素的吸收性质进一步扩展到六卤代芳烃，其中血红素仍然是这些有毒气体的强吸收候选物。血红素与卤代芳烃之间相互作用的详细研究表明，低自旋态和+3 和+4 氧化态的血红素都可以用作卤代芳烃的吸收剂。
