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Understanding the processes that occur during the redox transformations of complexes coordinated by redox-active apical ligands is important for the design of electrochemically active compounds with functional properties. In this work, a detailed analysis of the interaction energy and electronic structure was performed for cluster complexes trans-[Re6S8bipy4Cl2]n (n = 2–, 4–, 6–, 8–), which can be obtained by stepwise electrochemical reduction of a neutral cluster trans-[Re6S8bipy4Cl2] in DMSO solution. It was shown that the formation of open-shell paramagnetic ions with S = 1, 2 and 1 is the most energetically favorable for n = 2–, 4– and 6–, respectively. [ABSTRACT FROM AUTHOR]

We have studied the potential energy surface of [ M 2 D A B C O ] 4 + cations (M = Zn, Cd, and Hg), which are considered as a model for the DABCO linker in metal-organic frameworks, a new prospective class of materials. Relativistic four-component and two-component calculations of parity violating energy difference (PVED) for twisted isomers of [ M 2 D A B C O ] 4 + cations have been performed. The right-twisted conformers of [ M 2 D A B C O ] 4 + are more stable than the left-twisted ones. The increase in PVED with the nuclear charge of the transition metal atom M (ZM) is discussed. [ABSTRACT FROM AUTHOR]

The novel vanadium thiobromide, V(sub 4)S(sub 9)Br(sub 4), with a square-planner metal cluster core was synthesized and characterized by single-crystal X-ray diffraction, measurements of magnetic property and the heat capacity, and density functional theory (DFT) calculation of the electronic structure. The electronic structure of V(sub 4)S(sub 9)Br(sub 4) is characterized by a high spin state, that is, the electronic system is in the excited state.

Single crystals of Ta4S9Br8 are obtained by heating Ta, S, and Br2 and the structure is determined by X-ray analysis consisting of molecular clusters [Ta4(mu4-S)(mu-S2)4Br8]. The compound is soluble in CH3CN, giving a dark-red solution with a characteristic electronic spectrum, which is assigned on the basis of DFT calculations.

Temperature dependence of molar heat capacity Cp of Co2(C8H4O4)2·C6H12N2 was first measured by vacuum adiabatic calorimetry in the temperature range of 5.4–303 K. Two anomalies at 11 K and 80 K have been identified. The obtained Cp values were compared with those for Zn2(C8H4O4)2·C6H12N2 and Ni2(C8H4O4)2·C6H12N2. Spin–phonon interaction between lattice vibrations of Co2(C8H4O4)2.C6H12N2 and electron spins of Co2+ was revealed. [ABSTRACT FROM AUTHOR]

The optical properties of metal–organic frameworks [M2(bdc)2(dabco)] (M = Co, Ni, Cu, Zn) in the wavelength region of 300–1000 nm were studied, and the electronic band-to-band transitions were determined and characterized by the Kubelka–Munk approach and DFT calculations. Urbach edges for band-to-band transitions were determined. The effect of spin–phonon interactions on the width of Urbach edges in paramagnetic [M2(bdc)2(dabco)] is discussed. The obtained data may be useful to interpret polymerization, hybridization, and catalytic reactions in [M2(bdc)2(dabco)] pores and to design electronic and optical devices. [ABSTRACT FROM AUTHOR]

The article discusses the synthesis and the characterization of an organometallic trinuclear niobium cluster complex in aqueous solution. The significance of the presence of the [Nb.sub.3]([mu]-[n.sup.2]:[n.sup.2]-NCC[H.sub.3])[([mu.sub.2]-O).sub.3.sup.6)] cluster core in such complexes is also demonstrated.