Chemistry of binuclear bridged platinum metal complexes: VII. Quantum-chemical simulation of "Molecular assembling": Series [Ru(CN)(2)(py)(4)], [Cl(py)(4)Ru-NC-Ru(py)(4)CN](+), [Cl(py)(4)Ru-NC-Ru(py)(4)-CN-Ru(py)(4)Cl](2+)

CINDO+CI semiempirical calculations of the electronic spectra of the comple xes [Ru(CN)(2)(py)(4)], [Cl(py)(4)Ru-NC-Ru(py)(4)CN](+), and [Cl(py)(4)Ru-N C-Ru(py)(4)-CN-Ru(py)(4)Cl](2+) showed that the mononuclear fragments prese rve their features in the polynuclear complexes. The spectra of all the thr ee complexes are similar, which is due to the absence of intense interfragm ent excitations; the band splitting due to nonequivalence of the metal cent ers is insignificant. The preservation of the local electronic structure of the Ru-II(py)(4). (CN)(2) groups in the ground and electronically excited states makes them promising fragments of "molecular wires" in long-distance transfer of electron density and energy.