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Using benzene-diamine and benzene-dithiol molecular junctions as benchmarks, we investigate the widespread analysis of the quantum transport conductance $mathcal{G}(epsilon)$ in terms of the projected density of states (PDOS) onto molecular orbitals (MOs). We first consider two different methods for identifying the relevant MOs: 1) diagonalization of the Hamiltonian of the isolated molecule, and 2) diagonalization of a submatrix of the junction Hamiltonian constructed by considering only basis elements localized on the molecule. We find that these two methods can lead to substantially different MOs and hence PDOS. Furthermore, within Method 1, the PDOS can differ depending on the isolated molecule chosen to represent the molecular junction (e.g. benzene-dithiol or -dithiolate); and, within Method 2, the PDOS depends on the chosen basis set. We show that these differences can be critical when the PDOS is used to provide a physical interpretation of the conductance (especially, when it has small values as it happens typically at zero bias). In this work, we propose a new approach trying to reconcile the two traditional methods. Though some improvements are achieved, the main problems are still unsolved. Our results raise more general questions and doubts on a PDOS-based analysis of the conductance.
Forking structure is widespread in the open-source repositories and that causes a significant number of merge conflicts. In this paper, we study the problem of textual merge conflicts from the perspective of Microsoft Edge, a large, highly collaborat
The conductance of a molecular junction is commonly determined by either charge-transfer-doping, where alignment of the Fermi energy to the molecular levels is achieved, or tunnelling through the tails of molecular resonances within the highest-occup
We present a complete numerical calculation and an experimental data analysis of the universal conductance fluctuations in quasi-one-dimension nanowires. The conductance peak density model, introduced in nanodevice research on [Phys. Rev. Lett. 107,
The modified superexchange model is used to derive the expression for nonresonant tunneling conductance mediated by localized and delocalized molecular orbitals associated with the terminal and the interior molecular units respectively. The model is
We investigate the electrostatic confinement of charge carriers in a gapped graphene quantum dot in the presence of a magnetic flux. The circular quantum dot is defined by an electrostatic gate potential delimited in an infinite graphene sheet which