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Title: Effects of Size and Structural Defects on the Vibrational Properties of Lanthanum Hexaboride Nanocrystals

Authors:
; ; ; ORCiD logo
Publication Date:
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1358123
Grant/Contract Number:
AC02-05CH11231
Resource Type:
Journal Article: Published Article
Journal Name:
ACS Omega
Additional Journal Information:
Journal Volume: 2; Journal Issue: 5; Related Information: CHORUS Timestamp: 2017-12-08 09:59:57; Journal ID: ISSN 2470-1343
Publisher:
American Chemical Society (ACS)
Country of Publication:
United States
Language:
English

Citation Formats

Groome, Chloe, Roh, Inwhan, Mattox, Tracy M., and Urban, Jeffrey J.. Effects of Size and Structural Defects on the Vibrational Properties of Lanthanum Hexaboride Nanocrystals. United States: N. p., 2017. Web. doi:10.1021/acsomega.7b00263.
Groome, Chloe, Roh, Inwhan, Mattox, Tracy M., & Urban, Jeffrey J.. Effects of Size and Structural Defects on the Vibrational Properties of Lanthanum Hexaboride Nanocrystals. United States. doi:10.1021/acsomega.7b00263.
Groome, Chloe, Roh, Inwhan, Mattox, Tracy M., and Urban, Jeffrey J.. 2017. "Effects of Size and Structural Defects on the Vibrational Properties of Lanthanum Hexaboride Nanocrystals". United States. doi:10.1021/acsomega.7b00263.
@article{osti_1358123,
title = {Effects of Size and Structural Defects on the Vibrational Properties of Lanthanum Hexaboride Nanocrystals},
author = {Groome, Chloe and Roh, Inwhan and Mattox, Tracy M. and Urban, Jeffrey J.},
abstractNote = {},
doi = {10.1021/acsomega.7b00263},
journal = {ACS Omega},
number = 5,
volume = 2,
place = {United States},
year = 2017,
month = 5
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1021/acsomega.7b00263

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  • Syntheses of nanocrystalline perovskite phases of the general formula La{sub 1−x}Sr{sub x}MnO{sub 3+δ} were carried out employing sol–gel technique followed by thermal treatment at 700–900 °C under oxygen flow. The prepared samples exhibit a rhombohedral structure with space group R3{sup ¯}c in the whole investigated range of composition 0.20≤x≤0.45. The studies were aimed at the chemical composition including oxygen stoichiometry and extrinsic properties, i.e. size of the particles, both influencing the resulting structural and magnetic properties. The oxygen stoichiometry was determined by chemical analysis revealing oxygen excess in most of the studied phases. The excess was particularly high for themore » samples with the smallest crystallites (12–28 nm) while comparative bulk materials showed moderate non-stoichiometry. These differences are tentatively attributed to the surface effects in view of the volume fraction occupied by the upper layer whose atomic composition does not comply with the ideal bulk stoichiometry. - Graphical abstract: Evolution of the particle size with annealing temperature in the nanocrystalline La{sub 0.70}Sr{sub 0.30}MnO{sub 3+δ} phase. Display Omitted - Highlights: • The magnetic behaviour of nanocrystalline La{sub 1−x}Sr{sub x}MnO{sub 3+δ} phases was analyzed on the basis of their crystal structure, chemical composition and size of the particles. • Their Curie temperature and magnetization are markedly affected by finite size and surface effects. • The oxygen excess observed in the La{sub 1−x}Sr{sub x}MnO{sub 3+δ} nanoparticles might be generated by the surface layer with deviated oxygen stoichiometry.« less
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