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Discovery of space aromaticity in transition-metal monoxide crystal Nb3O3 enabled by octahedral Nb6 structural units
Zongxiang Hu1, Guoyu Qian1, Shunning Li1
1School of Advanced Materials, Peking University, Shenzhen Graduate School, Shenzhen 518055, China.
Abstract:
An octahedral Nb6 structural unit with space aromaticity is identified for the first time in a transition-metal monoxide crystal Nb3O3 by ab initio calculations. The strong Nb-Nb metallic bonding facilitates the formation of stable octahedral Nb6 structural units and the release of delocalization energy. Moreover, the Nb atoms in continuously connected Nb6 structural units share their electrons with each other in a continuous space of framework, so that the electrons are uniformly distributed. The newly discovered aromaticity in the octahedral Nb6 structural units extends the range of aromatic compounds and broadens our vision in structural chemistry.
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