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From the defects-free self-assembled organic layers (SAMs) of CH3([Formula: see text]SH molecules with short chain lengths ([Formula: see text]) electrodeposited on the (111) surface of monocrystalline gold previously prepared, monitored defects (pinholes) were potential-induced from cyclic partial reduction of SAMs at an appropriate potential. Electrochemical impedance measurements were in-situ conducted and [Fe(CN)6][Formula: see text] ions were used as probes for mass and charge transfer. Interface evolution was modeled with an equivalent electrical circuit containing two distinct constant-phase elements (CPEs). One is a generalized semi-infinite Warburg element in series with a charge transfer resistance attributed to subdiffusion phenomenon through leaky sublayers at low frequencies; the other CPE is used for characterizing the interface heterogeneity at medium and high frequencies. At low frequencies, electrochemical impedance measurements show subdiffusion phenomenon, which depends on the remaining sublayer and its thickness. When the defect density increases, diffusion tends to be ordinary, obeying the Fick’s law.

No abstract

We illustrate in this contribution the determination of the magnetic conductance across a nanocontact region defined by an isolated defect region joined between two mono-atomic leads ferromagnetically ordered. The system is described by the Heisenberg interaction. Additionally, to deal with the lack of symmetry across the contact region defined by the isolated defect, we involve the phase field matching approach. Furthermore, to compute the quantum conductance, we define the quantum scattering of the transmission and reflection probabilities within the framework of Landauer–Büttiker formalism. Based on these approaches, we present an analytical expression of the magnetic conductance. The obtained analytical results based on our adopted procedures confirm the known results adopted for perfect infinite leads (no defect). Our model calculations can be applied numerically when we deal with doping across the defect region. The adopted model could be also used numerically to deal with the impurity configurations that one might encounter in real systems.