RESUMO
We calculate the electronic and transport properties of a series of metalloporphyrin molecules sandwiched between gold electrodes using a combination of density functional theory and scattering theory. The impact of strong correlations at the central metallic atom is gauged by comparing our results obtained using conventional DFT and DFT + U approaches. The zero- and finite-bias transport properties may or may not show spin-filtering behavior, depending on the nature of the d state closest to the Fermi energy. The type of d state depends on the metallic atom and gives rise to interference effects that produce different Fano features. The inclusion of the U term opens a gap between the d states and changes the conductance and spin-filtering behavior qualitatively in some of the molecules. We explain the origin of the quantum interference effects found as due to the symmetry-dependent coupling between the d states and other molecular orbitals and propose the use of these systems as nanoscale chemical sensors. We also demonstrate that an adequate treatment of strong correlations is really necessary to correctly describe the transport properties of metalloporphyrins and similar molecular magnets.
RESUMO
Seven cases of DIC with cutaneous manifestations which permitted us to make the diagnosis. Etiopathogenic references are cited and the dermatological literature pointing out especially the cutaneous lesions with their clinical characteristics: ecchymoses which usually evolve to necrosis, bullae, petechiae, hematomas, cyanosis and bleeding at injection sites, and histological: Fibrinous thrombosis of the vessels of the dermis, with hemorrhages, necrosis and dermoepidermic bullae, with slight or no inflammation . In some of these cases the dermatological lesions antedated the characteristic laboratory data.
