The　electronic　structure　and　chemical　bonding　in　the　Ta3-　cluster　are　investigated　using　photoelectron　spectroscopy　and　density　functional　theory　calculations.　Photoelectron　spectra　are　obtained　for　Ta3-　at　four　photon　energies:　532,　355,　266,　and　193　nm.　While　congested　spectra　are　observed　at　high　electron　binding　energies,　several　low-lying　electronic　transitions　are　well　resolved　and　compared　with　the　theoretical　calculations.　The　electron　affinity　of　Ta3　is　determined　to　be　1.35　±　0.03　eV.　Extensive　density　functional　calculations　are　performed　at　the　B3LYP/Stuttgart　+2flg　level　to　locate　the　ground-state　and　low-lying　isomers　for　Ta3　and　Ta3-.　The　ground-state　for　the　Ta3-　anion　is　shown　to　be　a　quintet　(5A1′)　with　D3h,　symmetry,　whereas　two　nearly　isoenergetic　states,　C2v　(4Ai)　and　D3h6A/),　are　found　to　compete　for　the　ground-state　for　neutral　Ta3.　A　detailed　molecular　orbital　analysis　is　performed　to　elucidate　the　chemical　boding　in　Tas-,　which　is　found　to　possess　multiple　d-orbital　aromaticity,　commensurate　with　its　highly　symmetric　D3h,　structure.　©　2008　American　Chemical　Society.