Metal-Organic Frameworks (MOFs) of a Cubic Metal Cluster with Multicentered Mn(I)-Mn(I) Bonds.
MOFs with both multicentered metal-metal bonds and low-oxidation-state (LOS) metal ions have been underexplored hitherto. Here we report the first cubic [Mn(I) 8 ] cluster-based MOF (1) with multicentered Mn(I)-Mn(I) bonds and +1 oxidation state of manganese (Mn(I) or Mn(I)), as is supported by single-crystal structure determination, XPS analyses, and quantum chemical studies. Compound 1 possesses the shortest Mn(I)-Mn(I) bond of 2.372 Å. Theoretical studies with density functional theory (DFT) reveal extensive electron delocalization over the [Mn(I) 8 ] cube. The 48 electrons in the [Mn(I) 8 ] cube fully occupy half of the 3d-based and the lowest 4s-based bonding orbitals, with six electrons lying at the nonbonding 3d-orbitals. This bonding feature renders so-called cubic aromaticity. Magnetic properties measurements show that 1 is an antiferromagnet. This work is expected to inspire further investigation of cubic metal-metal bonding, MOF materials with LOS metals, and metalloaromatic theory.
Department of Chemistry, Key Laboratory of Advanced Energy Material Chemistry, Nankai University and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300071 (China).
Huan-Cheng
HC
Hu
Department of Chemistry, Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084 (China).
Han-Shi
HS
Hu
Department of Chemistry, Key Laboratory of Advanced Energy Material Chemistry, Nankai University and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300071 (China). zhaobin@nankai.edu.cn.
Bin
B
Zhao
Department of Chemistry, Key Laboratory of Advanced Energy Material Chemistry, Nankai University and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300071 (China).
Ping
P
Cui
Department of Chemistry, Key Laboratory of Advanced Energy Material Chemistry, Nankai University and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300071 (China).
Peng
P
Cheng
Department of Chemistry, Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084 (China). junli@tsinghua.edu.cn.
Jun
J
Li
antiferromagnets; cubic aromaticity; metal clusters; metal-organic frameworks; multicenter MnIMnI bonds