Electronic Structure of Li-Impurities in ZnSe.

1989 ◽  
Vol 163 ◽  
Author(s):  
T. Oguchi ◽  
T. Sasaki ◽  
H. Katayama-Yoshida
Keyword(s):  
Electronic Structures ◽  
Density Functional ◽  
Local Density ◽  
Lattice Relaxation ◽  
Interstitial Site ◽  
Functional Approach ◽  
Tetrahedral Interstitial Site ◽  
Total Energies ◽  
The Stability ◽  
Impurity Sites

AbstractElectronic properties of ZnSe with a Li impurity are investigated with use of the local-density-functional approach. The electronic structures are calculated for different impurity sites by taking the neighboring lattice relaxation into account. By comparing their total energies, the stability of the Li impurity in ZnSe is discussed. It is proposed that the Li impurity at the substitutional Zn site might be unstable to the tetrahedral interstitial site with an ionization of Li and a vacancy at the Zn site.

scholarly journals Lattice Location of Deuterium in Plasma and Gas Charged Mg Doped GaN

1999 ◽  
Vol 595 ◽  
Author(s):  
W. R. Wampler ◽  
J. C. Barbour ◽  
C. H. Seager ◽  
S. M. Myers ◽  
A. F. Wright ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Gas Phase ◽  
Density Functional ◽  
Lattice Relaxation ◽  
Functional Approach ◽  
Functional Theory ◽  
Ion Channeling ◽  
Total Energies ◽  
Lattice Locations ◽  
Mg Doped

AbstractWe have used ion channeling to examine the lattice configuration of deuterium in Mg doped GaN grown by MOCVD. The deuterium is introduced by exposure to gas phase or ECR plasmas. A density functional approach including lattice relaxation, was used to calculate total energies for various locations and charge states of hydrogen in the wurtzite Mg doped GaN lattice. Results of channeling measurements are compared with channeling simulations for hydrogen at lattice locations predicted by density functional theory.

ELECTRONIC STRUCTURES OF HEAVY-METAL CLUSTERS

1996 ◽  
Vol 03 (01) ◽  
pp. 335-340
Author(s):  
Y. ISHII ◽  
N. WATARI ◽  
S. OHNISHI
Keyword(s):  
Shell Model ◽  
Electronic Structures ◽  
Density Functional ◽  
Local Density ◽  
Model Description ◽  
First Principle ◽  
Electronic Shell ◽  
Hexagonal Close Packed ◽  
The Stability ◽  
Doubly Charged

The electronic structures of small Hg and Pb clusters are studied by the first-principle calculations within the local density-functional approximation. It is found that the stable structure of Hg19 cluster is not polyicosahedral but hexagonal close-packed although the bonding nature is still atom-like with no significant sp-hybridization. The stability of a doubly charged Pb cluster is discussed in connection with the electronic shell-model description. We conclude that the stability of Pb clusters is determined by complicated correlation between the atomic and electronic structures, and the electronic shell model cannot be applied straightforwardly.

scholarly journals Lattice Location of Deuterium in Plasma and Gas Charged Mg Doped GaN

2000 ◽  
Vol 5 (S1) ◽  
pp. 551-557
Author(s):  
W. R. Wampler ◽  
J. C. Barbour ◽  
C. H. Seager ◽  
S. M. Myers ◽  
A. F. Wright ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Gas Phase ◽  
Density Functional ◽  
Lattice Relaxation ◽  
Functional Approach ◽  
Functional Theory ◽  
Ion Channeling ◽  
Total Energies ◽  
Lattice Locations ◽  
Mg Doped

We have used ion channeling to examine the lattice configuration of deuterium in Mg doped GaN grown by MOCVD. The deuterium is introduced by exposure to gas phase or ECR plasmas. A density functional approach including lattice relaxation, was used to calculate total energies for various locations and charge states of hydrogen in the wurtzite Mg doped GaN lattice. Results of channeling measurements are compared with channeling simulations for hydrogen at lattice locations predicted by density functional theory.

Effect of the alloying element titanium on the stability and trapping of hydrogen in pure vanadium: A first-principles study

2014 ◽  
Vol 28 (29) ◽  
pp. 1450207 ◽  
Author(s):  
Juan Hua ◽  
Yue-Lin Liu ◽  
Heng-Shuai Li ◽  
Ming-Wen Zhao ◽  
Xiang-Dong Liu
Keyword(s):  
Binary Alloy ◽  
First Principles ◽  
Density Functional ◽  
Interstitial Site ◽  
Alloying Element ◽  
Functional Theory ◽  
Vacancy Defects ◽  
Tetrahedral Interstitial Site ◽  
The Stability ◽  
Insight Into

With a first-principles method based on density functional theory, the effect of the alloying element titanium ( Ti ) on the thermodynamic stability and electronic structure of hydrogen ( H ) in pure vanadium ( V ) is investigated. The interactions between H and the vacancy and the defect solution energies in a dilute V – Ti binary alloy are calculated. The results show that: (i) a single H atom prefers to reside in a tetrahedral interstitial site in dilute V – Ti binary alloy systems; (ii) H atoms tend to bond at the vacancy sites; a mono-vacancy is shown to be capable of trapping three H atoms; and (iii) the presence of Ti in pure V can increase the H trapping energy and reduce the H trapping capability of the vacancy defects. This indicates that doping with Ti to form dilute V – Ti binary alloys can inhibit the solution for H , and thus suppress the retention of H . These results provide useful insight into V -based alloys as a candidate structural material in fusion reactors.

The tuning effect of the electric field on the physical properties of some typical wurtzite semiconductors

2017 ◽  
Vol 31 (33) ◽  
pp. 1750310 ◽  
Author(s):  
Jia-Ning Li ◽  
San-Lue Hu ◽  
Hao-Yu Dong ◽  
Xiao-Ying Xu ◽  
Jia-Fu Wang ◽  
...  
Keyword(s):  
Electric Field ◽  
Physical Properties ◽  
First Principles ◽  
Electronic Structures ◽  
Density Functional ◽  
Great Influence ◽  
Semiconductor Materials ◽  
Functional Theory ◽  
The Stability ◽  
Wurtzite Semiconductors

Under the tuning of an external electric field, the variation of the geometric structures and the band gaps of the wurtzite semiconductors ZnS, ZnO, BeO, AlN, SiC and GaN have been investigated by the first-principles method based on density functional theory. The stability, density of states, band structures and the charge distribution have been analyzed under the electric field along (001) and (00[Formula: see text]) directions. Furthermore, the corresponding results have been compared without the electric field. According to our calculation, we find that the magnitude and the direction of the electric field have a great influence on the electronic structures of the wurtzite materials we mentioned above, which induce a phase transition from semiconductor to metal under a certain electric field. Therefore, we can regulate their physical properties of this type of semiconductor materials by tuning the magnitude and the direction of the electric field.

Electronic bonding characteristics of hydrogen in bcc iron: Part I. Interstitials

1996 ◽  
Vol 11 (9) ◽  
pp. 2206-2213 ◽  
Author(s):  
Yoshio Itsumi ◽  
D. E. Ellis
Keyword(s):  
Density Functional ◽  
Local Density ◽  
Lattice Relaxation ◽  
Experimental Result ◽  
Functional Formalism ◽  
Discrete Variational Method ◽  
Bcc Iron ◽  
Bond Strengths ◽  
Bonding Characteristics ◽  
Structure Calculations

Electronic structure calculations were carried out for bcc iron (Fe) clusters with or without hydrogen (H), and also involving a vacancy, using the self-consistent Discrete Variational method (DV-Xα) within the local density functional formalism. Bonding characteristics investigated show the following: (i) Interstitial H notably decreases interatomic Fe–Fe bond strengths, but acts over a small distance (within 0.3 nm). (ii) In the perfect Fe lattice field, interstitial H feels a repulsive force at any site. As a result of lattice relaxation, volume expansion may be expected. (iii) H in combination with a vacancy prefers a position shifted from the octahedral site toward the vacancy. This is fairly consistent with an experimental result.

Local-density-functional approach to all-trans-polyacetylene

1983 ◽  
Vol 28 (6) ◽  
pp. 3283-3290 ◽  
Author(s):  
J. W. Mintmire ◽  
C. T. White
Keyword(s):  
Density Functional ◽  
Local Density ◽  
Functional Approach ◽  
Local Density Functional
Sign in / Sign up

Export Citation Format

Share Document