This work presents the ab initio study of transition-metal phthalocyanines within a PBE0 hybrid functional. The list of metal impurities includes manganese, iron, cobalt, nickel, copper, and zinc. All calculations of isolated molecules have been performed with the use of the projector augment-wave method. For iron phthalocyanine, we have performed four calculations with different values of the mixing parameter a (the value of the exact exchange) – 0, 1/4, 1/3, and 1/2. For all other molecules, the calculations have been performed for a = 1/4 and 1/3. The electronic structure parameters including the HOMO-LUMO energy gap, Fermi level, magnetization, and imaginary part of the dielectric function are presented and compared with available theoretical and experimental data. Manganese, iron, and cobalt phthalocyanines show a strong dependence of electronic properties on the value of the exact exchange interaction. In other molecules with nickel, copper, and zinc, this dependence is not significant.

Ab initio investigation of the two porous coordination polymers Cu[Cu(pdt) 2 ] and Cu[Ni(pdt) 2 ] has been performed. The dispersion laws and partial density of states was obtained with the PBE0 hybrid functional. The results found here show that the materials under consideration are degenerate p-type semiconductors. Here, the effect of partial self-interaction removing of the strongly correlated 3d electrons of Cu and Ni was examined. In case of Cu-containing materials, the obtained results confirm that the 3d electrons of Cu reveal strong correlations, and, therefore, their electronic properties could be evaluated by means of a hybrid functional of the exchange-correlation energy. We also obtained quasiparticle properties within the Green's function (G0W0) and Bethe-Salpeter approaches. The last one was used in order to examine excitonic properties in the degenerate semiconductors. The imaginary part of the dielectric function was obtained within random-phase approximation as well as the Bethe-Salpeter approach.

First-principles calculations have been carried out to study the electronic properties of the KMgF3 perovskite crystal. On first stage the calculations were performed within the generalized gradient approximation. On the second stage we have evaluated the quasiparticle corrections to the generalized gradient approximation band structure. These significantly improved electronic energies have been found here for the first time on base of the quasiparticle approach as implemented in the ABINIT code. Also, the pressure dependent parameters of electronic energy band spectra were found in the generalized gradient approximation. For the first time the pressure dependent electronic band energies have been evaluated within the quasiparticle approach. The generalized gradient approximation band gap parameters are in good agreement with the literature data, obtained with local density approximation or generalized gradient approximation exchange-correlation functionals and are much underestimated compared with the experiment. The quasiparticle band gap agrees well with the measured value.

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