Crystal structure of <i>fac</i>-bis[bis(pyridin-2-yl)methanamine]iron(II) 1,1,3,3-tetracyano-2-(dicyanomethylidene)propane-1,3-diide, [Fe(dipa)<sub>2</sub>](tcpd)
Acta crystallographica. Section E, Crystallographic communications