𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Phase stability, electronic structure and mechanical properties of ternary-layered carbide Nb4AlC3: An ab initio study

✍ Scribed by Jiemin Wang; Jingyang Wang; Yanchun Zhou; Chunfeng Hu

Publisher
Elsevier Science
Year
2008
Tongue
English
Weight
794 KB
Volume
56
Category
Article
ISSN
1359-6454

No coin nor oath required. For personal study only.

✦ Synopsis

In this paper we calculated the phase stability, electronic structure and mechanical properties of Nb 4 AlC 3 by means of a first-principles pseudopotential total energy method. Based on thermodynamical calculations of the two possible crystal structures of Nb 4 AlC 3 , atype Nb 4 AlC 3 is confirmed to be the preferred equilibrium phase at ambient conditions. The chemical bonding displays layered characteristics that have commonly been reported for MAX ceramics. The equation of state and compressibility of a-Nb 4 AlC 3 were investigated. The material exhibits anisotropic elasticity under hydrostatic pressure: it is more compressible along the c direction than along the a and b directions. The second-order elastic coefficients, bulk modulus, shear modulus and Young's moduli were reported and compared with those of Nb 2 AlC. Since the salt-rock-type Nb-C slab is thicker in Nb 4 AlC 3 than that in Nb 2 AlC, the former material shows higher elastic stiffness than the latter one; at the same time, Nb 4 AlC 3 may display quasi-ductility, which has been well documented for MAX ceramics.

📜 SIMILAR VOLUMES

An ab initio study of the stability and
An ab initio study of the stability and electronic structure of univalent magnesium salts
✍ Paul G. Jasien; Clifford E. Dykstra 📂 Article 📅 1984 🏛 Elsevier Science 🌐 English ⚖ 484 KB

Large basis and weIl\_correiated ab initio electronic structure cdlcuiations have been performed on the simple h&(I) salts, h&F2 and Mg2CI,. The electron withdrswing power of the halogens gives rise to significant metal-metal bonding and consequently these as yet unobservccl. univalent salts are cal

An ab initio theoretical study of electr
An ab initio theoretical study of electronic structure and properties of 2′-deoxyguanosine in gas phase and aqueous media
✍ S. K. Mishra; P. C. Mishra 📂 Article 📅 2002 🏛 John Wiley and Sons 🌐 English ⚖ 177 KB 👁 1 views

## Abstract Molecular geometries of two structural forms of 2′‐deoxyguanosine (keto‐N9R and keto‐N7R, R = the sugar moiety) considering both the C2′‐endo and C3′‐endo conformations of the sugar ring and those of the complexes of these species with two water molecules each were optimized employing t

An ab-initio LCAO MO SCF study of the el
An ab-initio LCAO MO SCF study of the electronic structure and molecular properties of SF2
✍ Colin Thomson 📂 Article 📅 1976 🏛 Elsevier Science 🌐 English ⚖ 314 KB

Ab-initio calculations using three large gaussian basis sets arc reported for the unstable molecule SF2. The cffcct on tbc energy and computed geometry of polarhation functions and their expcrnents is examined, and a variety of one4cciron propertics computed.