1,2-Bis(dicyanomethylene)squarate

1,2-Bis(dicyanomethylene)squarate is a divalent anion with chemical formula C10N4O2−2 or ((N≡C−)2C=)2(C4O2)2−. It is one of the pseudo-oxocarbon anions, as it can be described as a derivative of the squarate oxocarbon anion C4O2−4 through the replacement of two adjacent oxygen atoms by dicyanomethylene groups =C(−C≡N)2.