Anomalous behavior of mercury in one dimension: Density-functional calculations

Abstract

We have investigated the effect of reduction of dimensionality on Zn, Cd, and Hg. Our results show that Hg stands out with uncommon properties in one dimension (1D). The overall trend has been reported for systems of group 8-12 elements all of which continue to be metallic in 1D too, with the exception of Hg: the interatomic distance (cohesive energy per bond) shows significant drop (rise) for all other systems at low dimensions. Hg linear chains settle for a larger interatomic distance, compared to the bulk or two-dimensional state, resulting in vanishing of the s-p band overlap robbing Hg of metallic property in 1D. Relativistic effects are shown to play a crucial role in this change of property.