Structure and magnetic properties of two cyanide-bridged one-dimensional M-CuII (M = FeIII or FeII) bimetallic assemblies from ferricyanide and CuN42+ (N4 = 1,4,8,11-tetraazacyclotetradecane and N,N′-bis(2-pyridyImethylene)-1,3-propanediamine) building blocks