title: All-metal antiaromatic molecule: rectangular Al4(4-) in the Li3Al4(-) anion.
abstract: We report the experimental and theoretical characterization of antiaromaticity in an all-metal system, Li3Al4(-), which we produced by laser vaporization and studied with the use of photoelectron spectroscopy and ab initio calculations. The most stable structure of Li3Al4(-) found theoretically contained a rectangular Al4(4-) tetraanion stabilized by the three Li+ ions in a capped octahedral arrangement. Molecular orbital analyses reveal that the rectangular Al4(4-) tetraanion has four pi electrons, consistent with the 4n Hückel rule for antiaromaticity.
authors.affiliation: Department of Chemistry and Biochemistry, Utah State University, Logan, UT 84322, USA.
authors.forename: Aleksey E
authors.initials: AE
authors.lastname: Kuznetsov
authors.forename: K Alexander
authors.initials: KA
authors.lastname: Birch
authors.forename: Alexander I
authors.initials: AI
authors.lastname: Boldyrev
authors.forename: Xi
authors.initials: X
authors.lastname: Li
authors.forename: Hua-Jin
authors.initials: HJ
authors.lastname: Zhai
authors.forename: Lai-Sheng
authors.initials: LS
authors.lastname: Wang