Projected surface energy bands, Shockley surface states, and bonding in transition-metal monocompounds with rock-salt structure: Example of NbC

1980 ◽  
Vol 17 (6) ◽  
pp. 1167-1177 ◽  
Author(s):  
Mojm�r Tom�?ek ◽  
?t?p�n Pick
Keyword(s):  
Transition Metal ◽  
Surface Energy ◽  
Rock Salt ◽  
Surface States ◽  
Energy Bands ◽  
Rock Salt Structure ◽  
Salt Structure

Li0.625Al0.125H0.25Cl0.75O0.25 Superionic Conductor with Disordered Rock-Salt Structure

2021 ◽  
Author(s):  
Qian Zhang ◽  
William Arnold ◽  
Zachary D. Hood ◽  
Yang Li ◽  
Rachel DeWees ◽  
...  
Keyword(s):  
Rock Salt ◽  
Superionic Conductor ◽  
Rock Salt Structure ◽  
Salt Structure

scholarly journals Subsolidus solution and ionic conductivity of rock-salt structured Li3+5xTa1−xO4 electroceramics

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
S. Shari ◽  
K.B. Tan ◽  
C.C. Khaw ◽  
Z. Zainal ◽  
O.J. Lee ◽  
...  
Keyword(s):  
Rock Salt ◽  
Xrd Analysis ◽  
Secondary Phases ◽  
Ionic Conductors ◽  
Rock Salt Structure ◽  
Conventional Solid State Reaction ◽  
Salt Structure ◽  
Crystallite Sizes ◽  
Symmetry Space ◽  
Symmetry Space Group

AbstractLithium tantalate solid solution, Li3+5xTa1−xO4 was prepared by conventional solid-state reaction at 925 °C for 48 h. The XRD analysis confirmed that these materials crystallized in a monoclinic symmetry, space group C2/C and Z = 8, which was similar to the reported International Crystal Database (ICDD), No. 98-006-7675. The host structure, β-Li3TaO4 had a rock-salt structure with a cationic order of Li+:Ta5+ = 3:1 over the octahedral sites. A rather narrow subsolidus solution range, i.e. Li3+5xTa1−xO4 (0 ⩽ x ⩽ 0.059) was determined and the formation mechanism was proposed as a replacement of Ta5+ by excessive Li+, i.e. Ta5+ ↔ 5Li+. Both Scherrer and Williamson-Hall (W-H) methods indicated the average crystallite sizes in the range of 31 nm to 51 nm. Two secondary phases, Li4TaO4:5 and LiTaO3 were observed at x = 0.070 and x = −0:013, respectively. These materials were moderate lithium ionic conductors with the highest conductivity of ~2.5 × 10−3 Ω 1 ˙cm−1 at x = 0, at 0 °C and 850 °C; the activation energies were found in the range of 0.63 eV to 0.68 eV.

scholarly journals Structural and Magnetic Properties of Mn-Based Diluted Magnetic Semiconductors and Alloys

2009 ◽  
Vol 2009 ◽  
pp. 1-4 ◽  
Author(s):  
A. Alsaad
Keyword(s):  
Rock Salt ◽  
Diluted Magnetic Semiconductors ◽  
Magnetic Semiconductors ◽  
Exchange Interactions ◽  
Magnetic Interactions ◽  
Local Spin Density Approximation ◽  
Energy Minimum ◽  
Rock Salt Structure ◽  
Magnetic Exchange ◽  
Salt Structure

Direct supercell approach calculations of the magnetic exchange interactions in Mn-doped ScN was carried out in the local spin density approximation by using the muffin-tin-orbital Green's function method. We found that magnetic interactions are long range interactions and affected by the randomness, band gap corrections, and carrier concentrations. Using total energy minimization approach we found that the global energy minimum of MnN is obtained for zinc-blende structure. If the compound is compressed by 6%, the energy minimum corresponds to the rock-salt structure in disagreement with the experimentally observed tetragonal distorted rock-salt structure, known as -phase. An isostructural phase transition for alloys from MnN -phase to -ScN phase was found to occur at a hydrostatic pressure of 18 GPa. We predict above room temperature for Mn concentrations of about 10% in ScN : Mn system.

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