Dimeric(RuPz)2 complex,modeling experimentally known dimers of(RuPor)2 and(RuPc)2,as well as its monomeric RuPz have been investigated using density functional theory[1].Pz,Por and Pc denote porphyrazine,porphyrin and phthalocyanine,respectively.It was shown that(RuPz)2 favors a Pz-Pz staggered conformer with the skew angle(N-Ru-Ru-N)= 33.3° rather than an eclipsed one,which is compared with experimental values of measured 23.8° for(RuOEPor)2 and assumed 45° for(RuPc)2.Structures of the staggered(RuPz)2 in all the possible electron-spin states as well as the RuPz were fully optimized.It was revealed that the(RuPz)2 has a ferromagnetic triplet ground state,being 6.3 kcal/mol lower than its diamagnetic singlet state,and 11.3~79.1 kcal/mol more stable than other states.This confirms experimentally reported(RuOEPor)2 and(RuPc)2 with magnetic moment of 2.5~2.8 μB.The Ru-Ru bond length of(RuPz)2 in the triplet state was optimized to be 2.38(A),close to experimental values of 2.40~2.41(A).The nature of Ru-Ru double bond has been evidenced by the calculated Ru-Ru stretching vibrational frequency of 202 cm-1 and bond energy of 30.7 kcal/mol(BSSE)at the theory level of larger basis sets.Associated with the continuum model,electronic spectra of(Py2RuPz),(PyRuPz)2 and(RuPz)2 which represent case of RuPz in the dilute solution,the concentrated solution and the solid state have been calculated and discussed in the work.