A first robust complex of tetradentate TCNQ. Evidence for two weakly coupled diruthenium(II,III) subsystems in symmetrical tetranuclear complexes (μ4-TCNX)[Ru(NH3)5]48+ (TCNX = TCNE, TCNQ). Inorganica Chimica Acta, (206)2:229--230, 1993. [PUMA: MO TCNQ complex complex;TCNE complex;frontier complex;magnetic complex;redox complex;spectra electronic moment potential ruthenium structure]