Origin of c-axis ultraincompressibility of Zr2InC above 70 GPa via first-principles

Abstract

The elastic and structural properties of nanolaminate Zr 2 InC are studied by first-principles, and it is shown that, for any used modes, including the generalized gradient approximation (GGA) and localized density approximation, there always exists an ultraincompressibility along c axis between 70 GPa and 400 GPa. Such anomalous behavior is originated from the slowdown of core-valence charge transfer. The rapid shift of Zr atom along c axis also contributed much to the ultraincompressibility as it is greatly reduced once the Zr atom shift suspends along c axis above about 400 GPa. Both the elastic constants and the phononic vibrational frequencies investigations confirmed the structural unstable simultaneously. The Poisson's ratio investigations observed a higher ionic or weaker covalent contribution in interatomic bonding and the degree of ionicity increases with pressure. V C 2013 AIP Publishing LLC. [http://dx.

Structural Transitions Induced by Ion Irradiation in V2AlC and Cr2AlC

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Anisotropic Elastic and Thermal Properties of M2InX (M = Ti, Zr and X = C, N) Phases: A First-Principles Calculation

“…At present, Z. J. Yang et al have carried out many theoretical studies on the novel hysteresis behavior of Zr 2 InC based on plane-wave pseudopotential (PW-PP) density functional theory (DFT) calculations, and the mechanical and electronic properties of Zr 2 InC under pressure were investigated using first principles [12]. A.D. Bortolozo et al investigated the Ti 2 InN phase by X-ray diffraction and magnetic and resistivity measurements, and the results clearly showed that Ti 2 InN is the first nitride superconductor belonging to the M n+1 AX n family [13].…”

Phase stability, mechanical properties and lattice thermal conductivity of ceramic material (Nb1−Ti )4AlC3 solid solutions

“…In the past decades, ternary carbides and nitrides ceramics known as the M n+1 AX n (MAX) phases (where n =1, 2, 3 or higher, M is an early transition metal atom, A is a group , , or elements and X is either C and/or N) have attracted much attention as promising engineering materials, due to their unique properties such as good electrical and thermal conductivity, damage tolerance, high melting point and excellent thermal shock resistance [1][2][3][4][5][6][7][8][9][10][11][12]. According to the value of layer index n, M n+1 AX n phases are labeled as 211, 312 and 413 phases for n=1, 2, 3, respectively.…”