The correlation between the electronic structure and elastic properties of nanolaminates

Abstract

Upon reviewing the correlation between the electronic structure and the elastic properties of nanolaminates based on the previously published ab-initio data, the authors suggest that nanolaminates can be described as interleaved layers of high and low electron density. Mn+1AXn phases (space group P63/mmc) can be characterized by stacking of layers of high (MX) and low (A) electron density. Furthermore, the Mn+1AXn phases possess the bulk-modulus-to-C44 ratio of 1.2–1.7, which in turn gives rise to a combination of ceramic and metallic properties. This design criterion is not only limited to the Mn+1AXn phases, but it can be found in many other phases crystallizing in the same space group (ternary phosphides, Al3BC3, Zr2Al3C5, and W2B5 based phases) and the related space group P6/mmm (Yn+1Co3n+5B2n) as well as in the phases of the cubic \( Pm\overline 3 m \) symmetry (perovskite borides and nitrides).