Elastic stability and electronic structure of tantalum boride investigated via first-principles density functional calculations

ABSTRACTYFe2H4 is a ferromagnetic metal with magnetization higher than the Laves phase parent compound, YFe2. Here, the electronic and magnetic properties of YFe2H4 are studied using density functional calculations, in order to elucidate the reasons for this. The electronic structure of YFe2H4 differs from that of YFe2 both because of the lattice expansion upon hydriding and because of chemical interactions involving H. However, the main reason for the increased magnetization is found to be the lattice expansion.

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Calculation of the Stability and the Polarizability of Isolated Fullerene Molecules as a Function of Charge State

MRS Proceedings ◽

10.1557/proc-270-209 ◽

1992 ◽

Vol 270 ◽

Author(s):

Andrew A. Quong ◽

Mark R. Pederson

Keyword(s):

Dielectric Constant ◽

Electronic Structure ◽

Simple Model ◽

First Principles ◽

Density Functional Calculations ◽

Density Functional ◽

Local Density ◽

Neutral Molecule ◽

Local Density Functional ◽

The Stability

ABSTRACTWe present first-principles local density functional calculations of the electronic structure and energetics of neutral and negatively charged fullerene molecules. We find thatthe negatively charged -1 state is stable relative to the neutral molecule and that the -2 state is stable relative to the neutral molecule but not to the -1 state of the molecule. We have also performed calculations of the electronic polarizabilities for different charged states and developed a simple model to estimate the dielectric constant of fullerene based crystals.

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Engineering of Graphene Band Structure by Haptic Functionalization

MRS Proceedings ◽

10.1557/opl.2012.711 ◽

2012 ◽

Vol 1407 ◽

Author(s):

Paul Plachinda ◽

Raj Solanki ◽

David Evans

Keyword(s):

Electronic Structure ◽

Band Structure ◽

Band Gap ◽

Metal Atom ◽

First Principles ◽

Density Functional Calculations ◽

Density Functional ◽

Electronic Devices ◽

Metal Carbonyl

ABSTRACTWe have employed first-principles density-functional calculations to study the electronic characteristics of graphene functionalized by metal-bis-arene and metal-carbonyl molecules. It is shown that functionalization with M-bis-arene (M(C6H6)@gr, M=Ti, V, Cr, Mn, Fe) molecules leads to an opening in the band gap of graphene (up to 0.81eV for the Cr derivative), and functionalization with M-carbonyl (M(CX)3@gr, X=O,N; M= Cr, Mn, Fe, Co) up to one 1eV for M=Cr and X=O, and therefore transforms graphene from a semi-metal to a semiconductor. The band gap induced by attachment of a metal atom topped by a functionalizing group is attributed to modification of π-conjugation and depends on the concentration of functionalizing molecules, metal’s and moiety’s electronic structure. This approach offers a means of tailoring the band structure of graphene and potentially its applications for future electronic devices.

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Magnetic Properties of Embedded Rh Clusters in Ni Matrix

MRS Proceedings ◽

10.1557/proc-384-535 ◽

1995 ◽

Vol 384 ◽

Author(s):

Zhi-Qiang Li ◽

Yuichi Hashi ◽

Jing-Zhi Yu ◽

Kaoru Ohno ◽

Yoshiyuki Kawazoe

Keyword(s):

Magnetic Properties ◽

Electronic Structure ◽

First Principles ◽

Density Functional ◽

Local Density ◽

Magnetic Moments ◽

Functional Formalism ◽

Rhodium Clusters ◽

Spin Polarized ◽

Local Density Functional

ABSTRACTThe electronic structure and magnetic properties of rhodium clusters with sizes of 1 - 43 atoms embedded in the nickel host are studied by the first-principles spin-polarized calculations within the local density functional formalism. Single Rh atom in Ni matrix is found to have magnetic moment of 0.45μB. Rh13 and Rhl 9 clusters in Ni matrix have lower magnetic moments compared with the free ones. The most interesting finding is tha.t Rh43 cluster, which is bulk-like nonmagnetic in vacuum, becomes ferromagnetic when embedded in the nickel host.

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Relativistic scalar and spin–orbit density functional calculations of the electronic structure, NICS index and ELF function of the [Re2(CO)8(μ-BiPh)2] and [Re2(CO)8(μ-BiPh2)2] clusters

Polyhedron ◽

10.1016/j.poly.2010.12.022 ◽

2011 ◽

Vol 30 (5) ◽

pp. 846-850 ◽

Cited By ~ 8

Author(s):

Eduardo Schott ◽

Ximena Zárate ◽

Ramiro Arratia-Pérez

Keyword(s):

Electronic Structure ◽

Density Functional Calculations ◽

Density Functional ◽

Spin Orbit

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Electronic structure of cubic BaTbO3 from first-principles pseudopotential calculations

Canadian Journal of Physics ◽

10.1139/p06-008 ◽

2006 ◽

Vol 84 (2) ◽

pp. 115-120 ◽

Cited By ~ 3

Author(s):

G Y Gao ◽

K L Yao ◽

Z L Liu

Keyword(s):

Electronic Structure ◽

First Principles ◽

Density Functional ◽

First Principles Calculations ◽

Generalized Gradient ◽

Functional Theory ◽

Exchange Correlation ◽

Pseudopotential Calculations ◽

Correlation Potential ◽

Density Contour

First-principles calculations of the electronic structure are performed for cubic BaTbO3 using the plane-wave pseudopotential method within the framework of density functional theory and using the generalized gradient approximation for the exchange-correlation potential. Our calculations show that cubic BaTbO3 is metallic, and that this metallic character is mainly governed by the Tb 4f electrons and the hybridization between the Tb 5d and O 2p states. From the analysis of the density of states, band structure, and charge density contour, we find that the chemical bonding between Tb and O is covalent while that between Ba and TbO3 is ionic. PACS Nos.: 71.15.Mb, 71.20.-b

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An electronic structure study of O-terminated zigzag BN nanotubes: Density functional calculations of the quadrupole coupling constants

Solid State Communications ◽

10.1016/j.ssc.2010.04.012 ◽

2010 ◽

Vol 150 (27-28) ◽

pp. 1238-1240 ◽

Cited By ~ 10

Author(s):

Maryam Mirzaei ◽

Mahmoud Mirzaei

Keyword(s):

Electronic Structure ◽

Density Functional Calculations ◽

Density Functional ◽

Structure Study ◽

Coupling Constants ◽

Quadrupole Coupling ◽

Bn Nanotubes

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Effect of Alloying Elements V, Cr and Ni on the Electronic Structure and Mechanical Properties of FeAl from First-Principles Calculation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.887-888.378 ◽

2014 ◽

Vol 887-888 ◽

pp. 378-383 ◽

Cited By ~ 2

Author(s):

Yu Chen ◽

Zheng Jun Yao ◽

Ping Ze Zhang ◽

Dong Bo Wei ◽

Xi Xi Luo ◽

...

Keyword(s):

Mechanical Properties ◽

Electronic Structure ◽

Elastic Constants ◽

First Principles ◽

Density Functional ◽

Valence Bond ◽

Ternary Alloys ◽

First Principles Calculation ◽

Structure Stability ◽

Alloying Element

The structure stability, mechanical properties and electronic structures of B2 phase FeAl intermetallic compounds and FeAl ternary alloys containing V, Cr or Ni were investigated using first-principles density functional theory calculations. Several models are established. The total energies, cohesive energies, lattice constants, elastic constants, density of states, and the charge densities of Fe8Al8 and Fe8XAl7 ( X=V, Cr, Ni ) are calculated. The stable crystal structures of alloy systems are determined due to the cohesive energy results. The calculated lattice contants of Fe-Al-X ( X= V, Cr, Ni) were found to be related to the atomic radii of the alloy elements. The calculation and analysis of the elastic constants showed that ductility of FeAl alloys was improved by the addition of V, Cr or Ni, the improvement was the highest when Cr was used. The order of the ductility was as follows: Fe8CrAl7 > Fe8NiAl7 > Fe8VAl7 > Fe8Al8. The results of electronic structure analysis showed that FeAl were brittle, mainly due to the orbital hybridization of the s, p and d state electron of Fe and the s and p state electrons of Al, showing typical characteristics of a valence bond. Micro-mechanism for improving ductility of FeAl is that d orbital electron of alloying element is maily involved in hybridization of FeAl, alloying element V, Cr and Ni decrease the directional property in bonding of FeAl.

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First-principles study of static displacements in Fe-Pd magnetic shape-memory alloys

MRS Proceedings ◽

10.1557/proc-1200-g04-04 ◽

2009 ◽

Vol 1200 ◽

Cited By ~ 1

Author(s):

Markus E. Gruner

Keyword(s):

Density Functional Theory ◽

Electronic Structure ◽

First Principles ◽

Density Functional ◽

First Principles Calculations ◽

Magnetic Shape Memory ◽

Magnetic Shape Memory Alloys ◽

Functional Theory ◽

Lennard Jones ◽

Theory Comparison

AbstractThis contribution reports static ionic displacements in ferromagnetic disordered Fe70Pd30 alloys obtained by relaxation of the ionic positions of a 108-atom supercell within the framework of density functional theory. Comparison with a simple statistical model based on Lennard-Jones pair interactions reveals that these displacements are significantly larger than can be explained by the different sizes of the elemental constituents. The discrepancies are presumably related to collective displacements of the Fe atoms. Corresponding distortions are experimentally observed for ordered Fe3Pt and predicted by first-principles calculations for all ordered Fe-rich L12 alloys with Ni group elements and originate from details of the electronic structure at the Fermi level.

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First-principles insights into ammonia decomposition on MoN (0001) surface

New Journal of Chemistry ◽

10.1039/d1nj02421c ◽

2021 ◽

Author(s):

kun yuan ◽

pengju hao ◽

Xiaolin Li ◽

Yang Zhou ◽

jiangbo zhang ◽

...

Keyword(s):

Density Functional Theory ◽

Electronic Structure ◽

Surface Energy ◽

Geometric Structure ◽

First Principles ◽

Density Functional ◽

Slab Model ◽

Ammonia Adsorption ◽

Functional Theory ◽

Dehydrogenation Mechanism

Density functional theory (DFT) and periodic slab model were used to study the geometric structure, electronic structure and dehydrogenation mechanism of ammonia adsorption on MoN (0001) surface. The surface energy...

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