hexakis(TPP-gold) carbide
Other names: hexa(auro)hexa(triphenylphosphine) carbide dication
[Au6(PPh3)6C]2+
47/50 
rare
There isn't any secret lore behind this unusual complex. There's a hexavalent carbide atom complexed by a highly symmetric octahedral gold cluster. I'm not going to lie to you and tell you it's a synthetically useful reagent or that it has particularly striking physical properties. It's an elegant and beautiful aurophilic gold coordination complex; what more do you want? What you see is what you get.