Electronic properties and ideal tensile strength of MoSe nanowires

Ab initio pseudopotential total energy calculations of MoSe nanowires were performed within the local density approximation. The Li2Mo6Se6 crystal is composed of molecular chains, which can be separated from one another to form individual nanowires approximately 3 Angstrom in diameter. In this study we consider three systems: the quasi-one-dimensional bulk crystal Li2Mo6Se6, one isolated MoSe nanowire, and one isolated MoSe nanowire with Li adsorbates. The equilibrium structures and the electronic structures of the three systems were calculated and compared to each other. The calculated density of states of an isolated MoSe wire is compared with experimental tunneling spectroscopy measurements of the local density of states. The binding energy of a Li atom to an isolated wire was calculated and the effects of Li adsorption are discussed. In addition, the calculated value for the ideal tensile strength of a single MoSe nanowire is presented and compared with estimated values for carbon nanotubes.