Structures and electronic properties of WmMon (m + n ≤ 7) clusters

2018 ◽  
Vol 32 (04) ◽  
pp. 1850041
Author(s):  
Zhicheng Yu ◽  
Xiurong Zhang ◽  
Peiying Huo ◽  
Kun Gao
Keyword(s):  
Ground State ◽  
Electronic Structures ◽  
Density Functional ◽  
Geometry Optimization ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
Ground State Structures ◽  
The Stability ◽  
D Orbitals

Geometric and electronic structures of W[Formula: see text]Mo[Formula: see text] (m + n [Formula: see text] 7) clusters have been systematically calculated by density functional theory (DFT) at the generalized gradient approximation (GGA) level for ground-state structures. Geometry optimization shows that clusters are almost bipyramid structures with m + n [Formula: see text] 4. E[Formula: see text] of clusters is mainly dominated by W atoms. And the substitution of atoms between W and Mo in Mo[Formula: see text] or W[Formula: see text] (n [Formula: see text] 7) clusters enhances the stability of the original clusters. The calculated IE shows that W[Formula: see text]Mo, W[Formula: see text]Mo2, W[Formula: see text]Mo3 and WMo[Formula: see text] are relatively more stable in the chemical reaction. In addition, the magnetism of clusters mainly comes from valance d orbitals.

scholarly journals Energetics and electronic structures of perylene confined in carbon nanotubes

2018 ◽  
Vol 5 (6) ◽  
pp. 180359 ◽  
Author(s):  
Yuya Nagasawa ◽  
Takeshi Koyama ◽  
Susumu Okada
Keyword(s):  
Carbon Nanotubes ◽  
Density Functional Theory ◽  
Ground State ◽  
Electronic Structures ◽  
Density Functional ◽  
Molecular Conformation ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Molecular Conformations ◽  
Generalized Gradient Approximation

The energetics and geometries of perylene encapsulated in carbon nanotubes (CNTs) have been investigated employing density functional theory using the generalized gradient approximation combined with the van der Waals correction. Our calculations show that the encapsulated perylene molecules possess two metastable molecular conformations with respect to the CNT wall, which are almost degenerate with each other. A standing conformation, with respect to the CNT wall, is the ground state conformation for a semiconducting (19,0)CNT, while a lying conformation is the ground state for a metallic (11,11)CNT. Cooperation and competition between perylene–perylene and perylene–CNT interactions cause these possible perylene conformations inside CNTs. However, the electronic structure of the CNT encapsulating the perylene molecules is found to be insensitive to the molecular conformation.

Structures and stabilities of (OsnN)0,±(n = 7 − 11) clusters

2015 ◽  
Vol 29 (23) ◽  
pp. 1550163
Author(s):  
W. L. Guo ◽  
L. L. Zhang ◽  
M. Luo ◽  
X. R. Zhang
Keyword(s):  
Density Functional Theory ◽  
Ionization Potential ◽  
Electron Affinity ◽  
Ground State ◽  
Density Functional ◽  
Magic Number ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
Ground State Structures

Structures and stabilities of [Formula: see text] clusters have been systematically studied via using density functional theory (DFT) with generalized gradient approximation (GGA). The calculations show that the stable configurations of [Formula: see text] are such structures with one N atom bonded to the external of the basic constructions consisting of Os atoms. Meanwhile, [Formula: see text] clusters [Formula: see text] represent “magic number” effect, and 8 is the magic number. Additionally, the ground-state structures of [Formula: see text] clusters have the best stability, while that of [Formula: see text] cluster possesses the worst stability. The result of the study on the ionization potential (IP) and the electron affinity (EA) shows that there are not topological differences among the configurations of [Formula: see text][Formula: see text] clusters.

Structure stability and magnetic properties of WnH2 (n =7–12) clusters

2015 ◽  
Vol 29 (27) ◽  
pp. 1550184 ◽  
Author(s):  
Xiang-Yu Zheng ◽  
Xiu-Rong Zhang ◽  
Ling-Ling Zhang ◽  
Gao-Kang Hu
Keyword(s):  
Magnetic Properties ◽  
Ground State ◽  
Density Functional ◽  
Structure Stability ◽  
Density Of State ◽  
Generalized Gradient ◽  
Electronic Density ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
Ground State Structures

In this paper, the structure and magnetic properties of WnH2 (n = 7–12) clusters have been systematically investigated using density functional theory (DFT) within the generalized gradient approximation (GGA). The result indicates that the ground state structures of WnH2 clusters are generated when H2 dissociative adsorbed on the atop site of Wn clusters. W8H2 and W[Formula: see text]H2 clusters are found to be more stable than other clusters. The adsorption abilities of Wn clusters are related to W–H bond length, adsorption energy and the charge transfer between H and W clusters as well as the electronic density of state.

scholarly journals Tuning Electronic Structures of BN and C Double-Wall Hetero-Nanotubes

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Xueran Liu ◽  
Meijun Han ◽  
Xinjiang Zhang ◽  
Haijun Hou ◽  
Shaoping Pang ◽  
...  
Keyword(s):  
Boron Nitride ◽  
Electric Field ◽  
Electronic Structures ◽  
Density Functional ◽  
Transverse Electric ◽  
First Principle ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
Double Wall

First principle calculations based on density functional theory with the generalized gradient approximation were carried out to investigate the energetic and electronic properties of carbon and boron nitride double-wall hetero-nanotubes (C/BN-DWHNTs) with different chirality and size, including an armchair (n,n) carbon nanotube (CNT) enclosed in (m,m) boron nitride nanotube (BNNT) and a zigzag (n, 0) CNT enclosed in (m, 0) BNNT. The electronic structure of these DWHNTs under a transverse electric field was also investigated. The ability to tune the band gap with changing the intertube distance (di) and imposing an external electric field (F) of zigzag DWHNTs provides the possibility for future electronic and electrooptic nanodevice applications.

Density Functional Calculations on Electronic and Magnetic Properties of Fe-Pt Systems

2005 ◽  
Vol 475-479 ◽  
pp. 3103-3106 ◽  
Author(s):  
You Song Gu ◽  
Jian He ◽  
Zhen Ji ◽  
Xiao Yan Zhan ◽  
Yue Zhang ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Magnetic Moment ◽  
Electronic Structures ◽  
Density Functional ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Exchange Correlation ◽  
Generalized Gradient Approximation ◽  
Experimental Values ◽  
Pseudo Potential

The electronic structures and magnetic properties of Fe-Pt systems were calculated by CASTEP codes, which employed density functional theory, generalized gradient approximation (GGA), Perdew Burke Ernzerh exchange correlation, Pulay density-mixing scheme and Ultra Soft pseudo potential. The band structures and density of states (DOS) were calculated, together with band populations and magnetic properties. The calculated results of α-Fe show the validatiy of this method in predication magnetic properties. It is found that as the Pt concentration increases, Fe 4s and 3d electrons decrease while 4p electrons increase, and the magnetic moment of Fe atom increases. Pt atoms also contribute to the magnetic moment due to polarization. The calculated magnetization agrees with experimental values quite well.

A comparative study of small 3d-metal oxide (FeO)n, (CoO)n, and (NiO)n clusters

2016 ◽  
Vol 18 (40) ◽  
pp. 27858-27867 ◽  
Author(s):  
G. L. Gutsev ◽  
K. G. Belay ◽  
K. V. Bozhenko ◽  
L. G. Gutsev ◽  
B. R. Ramachandran
Keyword(s):  
Density Functional Theory ◽  
Metal Oxide ◽  
Comparative Study ◽  
Electronic Structures ◽  
Density Functional ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Metal Oxide Clusters ◽  
Generalized Gradient Approximation

Geometrical and electronic structures of the 3d-metal oxide clusters (FeO)n, (CoO)n, and (NiO)n are computed using density functional theory with the generalized gradient approximation in the range of 1 ≤ n ≤ 10.

The Structure and Stability of C20 Dimer

2015 ◽  
Vol 1096 ◽  
pp. 228-231
Author(s):  
Ting Ting Dai ◽  
Pei Ying Huo ◽  
Ji Cai Yu ◽  
Huan Liu ◽  
Yan Xia Song ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Ground State ◽  
Electronic Structures ◽  
Density Functional ◽  
Ground State Structure ◽  
State Structure ◽  
Carbon Cage ◽  
Functional Theory ◽  
The Density Functional Theory ◽  
The Stability

The possible geometrical and electronic structures of C20dimer are optimized by using the density functional theory at B3LYP/LANL2DZ level, stable structure of C20dimer are obtained. The stability of the ground state structure have been studied. The results showed that: there was a slight expansion in carbon cage of C20 dimer ; its chemical stability and thermal stability have been improved.

Stability and Physicochemical Principles for Icosahedral Ti12X (X = Li to Xe) Clusters: A DFT Study

2008 ◽  
Vol 8 (5) ◽  
pp. 2475-2478
Author(s):  
M. Salazar-Villanueva ◽  
P. H. Hernandez Tejeda ◽  
J. F. Rivas-Silva ◽  
J. A. Ascencio
Keyword(s):  
Density Functional ◽  
Chemical Affinity ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
Stable Clusters ◽  
The Density Functional Theory ◽  
The Stability ◽  
Chemical Selectivity ◽  
Homo Lumo

Results about stability, electronic structure and characteristic electronic properties are reported for cluster structures based on icosahedra structure with a composition of Ti12X (X = Li to Xe) within the generalized gradient approximation of the density functional theory. It is demonstrated that several elements allow an improvement on the stability of Ti13 by a doping process where the central atoms is substituted. C, Si, P, Co, Ge, Ru and Te lead to the largest gain in energy, while the HOMO-LUMO maximum gap distinguishes to just C, Si, P and Te as the most probable to be found in experimental samples. The analysis included physicochemical study of the most stable clusters to predict chemical affinity and new properties. Results reported here are in agreement with partial studies of Ti12X but because of the considered elements, a new scope is open of possible application mainly in the fields as sensors, catalysis and medicine, where the chemical selectivity is an important parameter.

MOLECULAR ADSORPTION OF NO ON WmMon (m + n≤6) CLUSTERS

2019 ◽  
Vol 26 (06) ◽  
pp. 1850202
Author(s):  
ZHICHENG YU ◽  
XIURONG ZHANG ◽  
KUN GAO ◽  
PEIYING HUO
Keyword(s):  
Density Functional ◽  
Hollow Site ◽  
Generalized Gradient ◽  
Tungsten Atom ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
Nitric Oxide Adsorption ◽  
Ground State Structures ◽  
Back Donation ◽  
Geometric And Electronic Properties

Geometric and electronic properties of nitric oxide adsorption on WmMon ([Formula: see text] 6) clusters have been systematically calculated by density functional theory (DFT) at the generalized gradient approximation (GGA) level for ground-state structures. NO molecule prefers top site with nitrogen-end bridging a tungsten atom for W[Formula: see text]Mo[Formula: see text] and W3Mo2 clusters. While NO tends to locate on the hollow site for WMo5, W2Mo4 and W3Mo3 clusters, and dissociation of NO molecule happens on W3Mo, N–O bond lengths expand in accordance with the variation of adsorption energy with the increasing number of tungsten atoms, originating from metal [Formula: see text] back-donation. Electron transfer occurs among 4d state of Mo, 5d state of W, 2p state of N and 2p state of O.

FIRST-PRINCIPLES STUDY OF MAGNETISM AND DEFECT STATE PROPERTIES OF ANTIPEROVSKITE GaC1-xMn3

2010 ◽  
Vol 24 (10) ◽  
pp. 953-962 ◽  
Author(s):  
L. HUA ◽  
L. WANG ◽  
L. F. CHEN
Keyword(s):  
Ground State ◽  
First Principles ◽  
Density Functional ◽  
Unit Cell Volume ◽  
Magnetic Transition ◽  
Generalized Gradient ◽  
Functional Theory ◽  
Generalized Gradient Approximation ◽  
Spin Polarized ◽  
Volume Decrease

We have investigated the electronic and magnetic properties of GaC 1-x Mn 3 (x = 0, 0.125, 0.25) using first-principles density functional theory within the generalized gradient approximation (GGA) + U schemes. The crystal structures of the compounds are cubic for x = 0, 0.125, 0.25. The lattice parameters and unit cell volume decrease as the C vacancy increase. Our spin polarized calculations give metallic ground state for x = 0, 0.125, 0.25. The magnetic structure for x = 0, 0.125 are antiferromagnetic, while for x = 0.25 it is ferromagnetic. From the density of states (DOS), the hybridization between the C 2p and Mn 3d state is the main reason for magnetic transition.

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