Theoretical Modeling of the Oxidation of Hydrazine by Iron(II) Phthalocyanine in the Gas Phase. Influence of the Metal Character

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• 作者：Gloria I. Cá ; rdenas-Jiró ; n ; Veró ; nica Paredes-Garc&iacute ; a ; Diego Venegas-Yazigi ; José ; H. Zagal ; Maritza Pá ; ez ; Juan Costamagna
• 刊名：Journal of Physical Chemistry A
• 出版年：2006
• 出版时间：October 26, 2006
• 年：2006
• 卷：110
• 期：42
• 页码：11870 - 11875
• 全文大小：242K
• 年卷期：v.110,no.42(October 26, 2006)
• ISSN：1520-5215

文摘

The hydrazine oxidation by iron(II) phthalocyanine (Fe(II)Pc) has been studied using an energy profileframework through quantum chemistry theoretical models calculated in the gas phase at the density functionaltheory B3LYP/LACVP(d) level. We applied two models of charge-transfer mechanisms previously reported(J. Phys. Chem. A 2005, 109, 1196) for the hydrazine oxidation mediated by Co(II)Pc. Model 1 consists ofan alternated loss of one electron and one proton, involving anionic and neutral species. Model 2 considersan alternated loss of two electrons and two protons and includes anionic, neutral, and cationic species. Bothapplied models describe how the charge-transfer process occurs. In contrast with the obtained results forCo(II)Pc, we found that the hydrazine oxidation mediated by Fe(II)Pc is a fully through-bond charge-transfermechanism. On the other hand, the use of different charge-transfer descriptors (spin density, electronicpopulation, condensed Fukui function) showed a major contribution of the iron atom in comparison with thecobalt atom in the above-mentioned process. These results could explain the higher catalytic activity observedexperimentally for Fe(II)Pc in comparison with Co(II)Pc. The applied theoretical models are a good startingpoint to rationalize the charge-transfer process of hydrazine oxidation mediated by Fe(II)Pc.