Detection of the Elusive Highly Charged Zintl Ions Si4 (4-) and Sn4 (4-) in Liquid Ammonia by NMR Spectroscopy.

Abstract

It's detected! The existence of the prototypical Zintl ions Tt4 (4-) (Tt=Group 14 element), which are isoelectronic to the P4 molecule, used to be confined to the solid state. Recently, circumstantial evidence for a solution chemistry in liquid ammonia emerged. Direct spectroscopic observation of the dissolved anions has now been achieved. In the case of Si4 (4-) , this is the first solution detection of any homoatomic silicide.