The magnetic properties of CoN clusters (N=1, 13, 19, and 43) embedded in copper matrix are studied using the discrete-variational local-spin-density-functional method and embedded cluster models. Single Co atom in Cu is found to be nonmagnetic, while all the rest Co clusters in Cu are still magnetic with reduced moments. Cu atoms in granular Co/Cu system reveal similar spin polarizations to Cu atoms in Co/Cu multilayers as manifested in recent x-ray magnetic circular dichroism measurements.

Density functional theory (DFT) calculations are performed to study the Y4O molecule in its neutral, anionic, and cationic states. The equilibrium geometries of Y4O, Y4Oˉ, and Y4O+ are trigonal bi-pyramids. The ground states of Y4O, Y4Oˉ, and Y4O+ are triplet (3A1), doublet (2A00), and doublet (2A0), respectively. Time-dependent DFT is used to calculate the excited states. A theoretical assignment for the features in the experimental photoelectron spectrum is given. All results obtained are in good agreement with the available experimental data.

Metal-free and copper porphyrazines, [H2pz] and [Cu pz], have been fused at the periphery with molybdocene dithiolene, [Cp2Mo]. The optical, magnetic, and electronic properties of the resulting neutral and cationic complexes are studied, using first-principles density functional theory implemented by the discrete variational method. Analysis of the charge and spin distribution shows that the porphyrazine core is strongly coupled with the peripheral complex. The calculated optical absorption is found to be in reasonable agreement with experimental spectra, lending support to our theoretical model. Under appropriate circumstances one observes interaction of unpaired pins localized in the vicinity of both metal sites. The calculated spin distribution shows that [Cp2Mo] [Cu pz] and [Cp2Mo] [H2pz]+ have a magnetic moment of 1μB while [Cp2Mo] [Cu pz]+ and [Cp2Mo] [H2pz] have no moment, in good agreement with the results of X-band EPR spectra. The Cu-Mo magnetic interaction is antiferromagnetic, being mediated by pyrrol nitrogens, meso nitrogens, carbons, and sulfurs.

The compound (Cu (pc)) 3 (ReO4) 2 (pc=phthalocyaninato) has been prepared by electrocrystallization from a p-dichlorobenzene solution of Cu (pc) and [N (n-Bu) 4] [ReO4]. (Cu (pc)) 3 (ReO4) 2 crystallizes with one formula unit in the triclinic space group P1h with cell constants at T=153K of a=12.6202 (6)Å, b=13.7596 (7)Å, c=14.0294 (7)Å, R=64.6376 (9)°, β=64.2570 (9)°, and γ=66.0549 (9)°. The molecular structure comprises a stack of three Cu (pc) rings; the Cu center in each peripheral ring has an attached ReO4 ligand, the Cu-O distance being 2.374 (5)Å. The inter-ring distance is 3.1595 (11)Å. Density functional theory calculations for Cu (pc) (ReO4) and Cu (pc) (ReO4) 2 suggest that the ring-Ω states are the source of the electron donation to the ligands. Calculations for (Cu (pc)) 3 (ReO4) 2 suggest that the charges on the central and peripheral rings are nearly equal. For all three compounds the basic spin distributions are similar to each other and to those of other Cu (pc) systems. For (Cu (pc)) 3 (ReO4) 2 a localized, rather than an itinerant, description of the magnetism is indicated.

The electron affinities and low-lying excited states of all the 3d transition metal monoxide molecules are studied using the density functional theory (DFT) and time-dependent (TD) DFT method. The calculated results are compared with the available theoretical ones and used to assign the features of these monoxides in photoelectron spectroscopies. It shows that TDDFT, by and large, can be used to get good results for the excited states of the open-shell transition metal oxides. The effect of basis sets on the calculated results is also discussed.