All-Metal Antiaromatic Molecule: Rectangular Al₄^4- in the Li₃Al₄^- Anion

Aleksey E. Kuznetsov, K. Alexander Birch, Alexander I. Boldyrev, Xi Li, Hua-Jin Zhai, and Lai-Sheng Wang
Science 2003 April 25; 300: 622-625. (in Reports)