Interplay between structural and electronic properties of bundledMo6S9 − xIx nanowires

Abstract

Using first principles density functional theory, we investigate thestructural, electronic and magnetic properties of isolated and bundledMo6S9 − xIx nanowireswith x = 3, 4.5, and 6. The unit cell of each system contains twoMo6 octahedra decorated with S and I atoms and twoS3 linkages. Due to the bistability of each sulfur linkage, finite-length nanowires or nanowirebundles exhibit many stable structural minima. We explore the structural stability,elastic behavior and electronic structure at all these minima for each compositionx. We find that the axial strain and inter-wire interaction in bundles significantly modifythe electronic structure. The most intriguing changes occur in nanowires withx = 4.5 and 6, which change from metal to semiconductor or undergo a magnetic transition uponaxially stretching or compressing the nanowires or upon changing the inter-wire separation.