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arXiv · 1703.04903

Ultrashort Mn-Mn Bonds in Organometallic Complexes

Tomás Alonso-Lanza·Jhon W. González·Faustino Aguilera- Granja·Andrés Ayuela
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Abstract

Manganese metallocenes larger than the experimentally produced sandwiched MnBz$_2$ compound are studied using several density functional theory methods. First, we show that the lowest energy structures have Mn clusters surrounded by benzene molecules, in so-called rice-ball structures. We then find a strikingly short bond length of 1.8 {\AA} between pairs of Mn atoms, accompanied by magnetism depletion. The ultrashort bond lengths are related to Bz molecules caging a pair of Mn atoms, leading to a Mn-Mn triple bond. This effect is also found when replacing benzenes by other molecules such as borazine or cyclopentadiene. The stability of the Mn-Mn bond for Mn$_2$Bz$_2$ is further investigated using dissociation energy curves. For each spin configuration, the energy versus distance plot shows different spin minima with barriers, which must be overcome to synthesize larger Mn-Bz complexes.

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Tomás Alonso-Lanza, Jhon W. González, Faustino Aguilera- Granja, Andrés Ayuela. 2017-03-15. Ultrashort Mn-Mn Bonds in Organometallic Complexes. https://arxiv.org/abs/1703.04903

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