New examples of metalloaromatic Al-clusters: (Al4M4)Fe(CO)3 (M=Li, Na   and K) and (Al4M4)2Ni: Rationalization for possible synthesis
  Ab-initio calculations reveal that all-metal antiaromatic molecules like Al4M4 (M=Li, Na and K) can be stabilized in half-sandwich complex: (Al4M4)Fe(CO)3 and full-sandwich complexes of the type: (Al4M4)2Ni. The formation of the full-sandwich complex [(Al4M4)2Ni] from its organometallic precursor depends on the stability of the organic-inorganic hybrid (C4H4) Ni (Al4Li4). 
Ayan Datta and Swapan K. Pati