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Title: Ab initio Modeling of the Electronic Structures and Physical Properties of a-Si 1− x Ge x O 2 Glass ( x = 0 to 1)

Authors:
 [1];  [1];  [1];
  1. Department of Physics and Astronomy, University of Missouri-Kansas City, Kansas City Missouri 64110
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1400574
Grant/Contract Number:
SC008176; AC03-76SF00098
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Journal of the American Ceramic Society
Additional Journal Information:
Journal Volume: 99; Journal Issue: 11; Related Information: CHORUS Timestamp: 2017-10-20 15:26:42; Journal ID: ISSN 0002-7820
Publisher:
Wiley-Blackwell
Country of Publication:
United States
Language:
English

Citation Formats

Baral, Khagendra, Adhikari, Puja, Ching, Wai-Yim, and Sinnott, ed., S. Ab initio Modeling of the Electronic Structures and Physical Properties of a-Si 1− x Ge x O 2 Glass ( x = 0 to 1). United States: N. p., 2016. Web. doi:10.1111/jace.14386.
Baral, Khagendra, Adhikari, Puja, Ching, Wai-Yim, & Sinnott, ed., S. Ab initio Modeling of the Electronic Structures and Physical Properties of a-Si 1− x Ge x O 2 Glass ( x = 0 to 1). United States. doi:10.1111/jace.14386.
Baral, Khagendra, Adhikari, Puja, Ching, Wai-Yim, and Sinnott, ed., S. Thu . "Ab initio Modeling of the Electronic Structures and Physical Properties of a-Si 1− x Ge x O 2 Glass ( x = 0 to 1)". United States. doi:10.1111/jace.14386.
@article{osti_1400574,
title = {Ab initio Modeling of the Electronic Structures and Physical Properties of a-Si 1− x Ge x O 2 Glass ( x = 0 to 1)},
author = {Baral, Khagendra and Adhikari, Puja and Ching, Wai-Yim and Sinnott, ed., S.},
abstractNote = {},
doi = {10.1111/jace.14386},
journal = {Journal of the American Ceramic Society},
number = 11,
volume = 99,
place = {United States},
year = {Thu Jul 28 00:00:00 EDT 2016},
month = {Thu Jul 28 00:00:00 EDT 2016}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1111/jace.14386

Citation Metrics:
Cited by: 7works
Citation information provided by
Web of Science

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  • Ab-initio electronic structure calculations are carried out for quinternary Fe{sub 2}Mn{sub 1−x}V{sub x}Si{sub 0.5}Al{sub 0.5} alloys. When x=0 the alloy is half-metallic ferromagnet, with magnetic moment following the Slater–Pauling rule. Replacement of Mn by V, changes its electronic and magnetic structure. V-doped alloys exhibit half-metallic behavior for x≤0.25. However, even for higher V concentrations, electronic spin polarization is still very high, what makes the alloys interesting for spintronic applications. - Graphical abstract: Densities of states of Fe{sub 2}MnSi{sub 0.5}Al{sub 0.5} and magnetic moments of Fe{sub 2}Mn{sub 1−x}V{sub x}Si{sub 0.5}Al{sub 0.5}. - Highlights: • Fe{sub 2}MnSi{sub 0.5}Al{sub 0.5} is a half-metallicmore » ferromagnet with a minority band gap of 0.49 eV. • Half-metallic band gap is very stable against the change of the lattice parameter. • Half-metallic band gap is obtained for Fe{sub 2}Mn{sub 1−x}V{sub x}Si{sub 0.5}Al{sub 0.5} for x≤0.25. • Electronic spin polarization is very high and equal to at least 95% for x≤0.625. • The main carrier of magnetism of the compound is manganese.« less
  • The reaction of N-n-Bu/sub 4/MnO/sub 4/ with appropriate reagents in nonaqueous solvents leads to the high-yield formation of trinuclear oxo-centered Mn complexes of general formulation (Mn/sub 3/O(O/sub 2/CR)/sub 6/L/sub 3/)/sup z+/ (1, R = Me, L = pry, z = 1; 2, R = Me, L = pyr, z = 0, monopyridine solvate; 3, R = Me, L = pyr, z = 0, unsolvated; 4, R = Ph, L/sub 3/ = (pyr)/sub 2/(H/sub 2/O), z = 0; 5, R = Me, L = HIm, z = 1; pyr = pyridine, HIm = imidazole). The crystal structures of complexes 2 andmore » 4 have been determined. Complex 2 crystallizes in rhombohedral space group R32 with (at -50 /sub 0/C) a = b = 17.552 (6) A, c = 10.918 (3) A, ..gamma.. = 120.00 (1)/sup 0/, and Z = 3. A total of 1546 unique data with F > 3sigma(F) were refined to conventional values of R and R/sub w/ of 5.77 and 5.86%, respectively. Complex 4 crystallizes in monoclinic space group P2/sub 1/ with (at -156 /sup 0/C) a = 15.058 (10) A, b = 23.600 (17) A, c = 14.959 (10) A, ..beta.. = 91.01 (3)/sup 0/, and Z = 2. Both 2 and 4 posses an oxo-centered Mn/sub 3/O unit characteristic of basic carboxylates with peripheral ligation provided by bridging carboxylate and terminal pyr (or H/sub 2/O) groups.« less
  • Cited by 3
  • Crystallographic and magnetic properties of bulk Co{sub 2}Fe(Ge{sub 1−x}Si{sub x}) alloys with 0 ≤ x ≤ 1, synthesized by arc melting method, have been studied. Co{sub 2}FeSi alloy has been found to crystallize with L2{sub 1} structure, but the super-lattice peaks are absent in the X-ray diffraction patterns of alloys containing high Ge concentration. Unit cell volume of this series of alloys decreased from 185.2 to 178.5 Å{sup 3} as Si content was increased from 0 to 1.00. All alloy compositions exhibit ferromagnetic behavior with a high Curie temperature (T{sub C}). T{sub C} showed a systematic variation with x. A comparison between the valuesmore » of saturation magnetization (M{sub s}) and effective moment per magnetic atom p{sub c} estimated from the temperature dependent susceptibility data above T{sub C}, shows that the alloys have half-metallic character. The alloy with x = 0 follows Slater-Pauling (S-P) rule with M{sub s} of 5.99μ{sub B}. However, M{sub s} for the alloy with x = 1.00 was found to be 5.42μ{sub B}, which is lower than the value of 6.0μ{sub B} predicted by S-P rule. Since atomic disorder is known to affect the M{sub s} and electronic structure of these alloys, ab initio calculations were carried out to explain the deviation in observed M{sub s} from S-P rule prediction and the half-metallic character of the alloys. Ab initio calculations reveal that alloys with L2{sub 1} structure have M{sub s} value as predicted by S-P rule. However, introduction of 12.5% DO{sub 3} disorder, which occurs due to swapping of Co and Fe atoms in the unit cell, decreases M{sub s} of alloys with x > 0 from the S-P prediction to values obtained experimentally. The results analyzed from the view point of electronic structure of the alloys in different ordered states bring out the influence of disorder on the observed magnetic properties of these technologically important alloys.« less