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Li, Hongtao; Feng, Jingdong; Zhang, Wenqing; Jiang, Wan; Gu, Hui; Smith, J. R.

doi:10.1103/physrevb.80.205422

Cited by 10 publications

(7 citation statements)

References 56 publications

(70 reference statements)

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“…These structural distortions could be expected from a simple ionic radii size effect analysis, since the ionic radius for sixfold coordinated Al +3 is 0.55Å, which is smaller than the 0.95Å value for Cd +2 . 57 As it has been observed previously in Cd-doped In 2 Fig. 4(a) 18,40 the Cd-5p contribution dominates over the d contribution, which is due to the fact that the first node of the 5p wave function is at a much shorter distance than the one of the 4d wave function, is important in the case of O2 while it is negligible in the case of O1 which is related to the fact that, after structural relaxation, the Cd-O1 bonds are mostly in the x-y plane [a-b plane in Fig.…”

Section: Substitutional CDsupporting

confidence: 63%

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Site localization of Cd impurities in sapphire

et al. 2012

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By combining first-principles electronic structure calculations and existing time-differential γ -γ perturbedangular-correlation experiments we studied the site localization, the local environment, and the electronic structure of Cd impurities in sapphire (α-Al 2 O 3 ) single crystals in different charged states. The ab initio calculations were performed with the full-potential augmented plane wave plus local orbitals method and the projector augmented wave method. Comparing the calculated electric-field-gradient tensor at the Cd nuclei in the α-Al 2 O 3 host lattice and the corresponding available experimental values, we have seen that it is equally possible for Cd to replace an Al atom (in a negative charge state) or to be placed in an interstitial site (in a neutral charge state). To finally address the issue of the Cd impurity localization, we performed formation energy calculations. These results have shown that Cd placed in the substitutional Al site, in the negatively charged state, is the most probable configuration.

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Section: Substitutional CDsupporting

confidence: 63%

“…30 and 31, the EFG sign can only be determined performing a nonstandard γ -γ TDPAC experiment, in which the polarization of the second γ ray has to be measured. Further RBS/C measurements, in the same conditions as the TDPAC experiments, i.e., with the same implantation energy, dose, thermal annealing, and composition of the α-Al 2 …”

Section: Discussionmentioning

confidence: 99%

Site localization of Cd impurities in sapphire

et al. 2012

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“…The projector augmented plane wave method 44,45 with a plane wave energy cut off of 500 eV and an energy convergence criterion of 10 −4 eV is used. Readers interested in additional details about the density‐functional computational details used here can read about them in Zhang and colleagues 33–36,46 …”

Section: First‐principles Work Of Separationmentioning

confidence: 99%

“… For the β‐Ni 1− x Al x /α–Al 2 O 3 interfaces, 46 n ws is approximately taken to be the average value of the parameters for pure Ni and Al to evaluate the W sep of the Al 2 term –1Al interface, and the n ws of Ni is used to evaluate W sep of the O term –8Al interface due to the presence of Ni‐rich layer in the β‐NiAl–Ni rich slab (see Table I). …”

Section: Analytical Relationships For Stoichiometry‐dependent Womentioning

confidence: 99%

“…The solid line corresponds to the linear fit to all the data for type‐I M/(Al 2 O 3 ) Al2 interfaces. The W sep corresponding to the cleavage β‐NiAl/(Al 2 O 3 ) Al2 for the Al 2 term –1Al interface, and β‐NiAl‐Ni rich /(Al 2 O 3 ) Al2 for the O term –8Al are also plotted in the figure 46 …”

Section: Analytical Relationships For Stoichiometry‐dependent Womentioning

confidence: 99%

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Interfacial Stoichiometry and Adhesion at Metal/α‐Al₂O₃ Interfaces

Chen

Yuan

et al. 2011

J. Am. Ceram. Soc.

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First-principles studies of metal/a-Al 2 O 3 interfaces have revealed strong interfacial stoichiometry effects on adhesion. The metals included Al, Ni, Cu, Au, Ag, Rh, Ir, Pd, Pt, Nb, and b-NiAl. Metallic and ionic-covalent adhesive bonding effects were found in varying amounts depending on whether the interfacial stoichiometry is stoichiometric, oxygen-rich, or aluminum-rich in a qualitative way. A semiempirical but physically sensible understanding ensues for the effects of interfacial stoichiometry and reveals the underlying strong correlation of the interfacial adhesion with the physical properties of the bulk materials that join and form the interface. The metallic component of the bonding was found to be related to the ratio of (B/V) 1/2 , where B and V are the bulk modulus and molar volume of the metal, respectively. In like manner, the ionic-covalent component of the bonding could be related to the enthalpy of oxide formation of the bulk metal. A unified model is proposed to describe the adhesion of metal/alumina interfaces with interfacial stoichiometry effects, and the model is also expected to be valid for other metal-oxide interfaces.M. Ru¨hle-contributing editor

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Advances in ab initio thermodynamic studies on metal/oxide interfaces

Zhang

Smith

2011

Physica Status Solidi (a)

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We provide a brief overview of the advances in ab initio thermodynamic studies on metal/oxide interfaces in this paper. Firstly, the development in interface modeling is briefly outlined. Secondly, the fundamentals of ab initio thermodynamic method are described. Thirdly, ab initio thermodynamic studies on several typical interfaces between alumina and metals including alloys are presented, especially for the interfaces between α‐Al2O3 and Nb, Ni, Cu, and β‐Ni1−xAlx alloy. Finally, through analyzing electronic structure, chemical bonding, and adhesion of the interfaces between α‐Al2O3 and a series of metals, including Al, Ni, Cu, Au, Ag, Rh, Ir, Pd, Pt, Nb, and β‐NiAl, a formally unified model is derived for evaluating the works of separation of the representative aluminum‐rich, oxygen‐rich, and stoichiometric metal/α‐Al2O3 interfaces. This model is also expected to be valid for studying other metal/oxide interfaces.

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Ab initiothermodynamic study of the structure and chemical bonding of aβ-Ni1−xAlx/α-Al2<

Cited by 10 publications

References 56 publications

Site localization of Cd impurities in sapphire

Site localization of Cd impurities in sapphire

Interfacial Stoichiometry and Adhesion at Metal/α‐Al₂O₃ Interfaces

Advances in ab initio thermodynamic studies on metal/oxide interfaces

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Ab initiothermodynamic study of the structure and chemical bonding of aβ-Ni1−xAlx/α-Al2<

Cited by 10 publications

References 56 publications

Site localization of Cd impurities in sapphire

Site localization of Cd impurities in sapphire

Interfacial Stoichiometry and Adhesion at Metal/α‐Al2O3 Interfaces

Advances in ab initio thermodynamic studies on metal/oxide interfaces

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Product

Resources

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Interfacial Stoichiometry and Adhesion at Metal/α‐Al₂O₃ Interfaces