The 4,5,6-triphospha[3]radialene dianion: a phosphorus analogue of the deltate dianion.  A NICS(0)(πzz) examination of their aromaticity. 
Reduction of a 4,5,6-triphospha[3]radialene gave the corresponding isolable dianionic species.  Despite having two deltate dianion-like π-electrons delocalized over the central framework, its small NICS(0)(πzz) value (only -2.2 ppm) indicates only limited aromaticity.