ISSN:
1013-9826
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
The effects of A-site cation size disorder in ABO3 type ferromagnetic metallicLa0.55Ca0.45MnO3 system have been studied by substituting La3+ and Ca2+ by other ions, while keepingthe valency of Mn ions and the A-site cation mean radius 〈rA〉 constant in the substituted compoundswith different A-site ionic radii variance σ2 = Σi (xiri2 − 〈rA〉2), where xi and ri are the atomic fraction andionic radii of i-type ions at A-site, respectively. It is revealed that the A-site disorder induces thedecreasing of the magnetization and the increasing of the resistivity. The ferromagnetic Curie point TCdecreases with the increasing of the A-site ionic radii variance, too. Moreover, the ground state of thesystem transits from ferromagnetic metal to glass insulator upon increasing variance of the A-site ionicradii from 0.0003 for La0.55Ca0.45MnO3 to 0.009 for Gd0.55Sr0.45MnO3. It is argued that the suppression ofthe ferromagnetism is ascribed to the enhanced radial distortion of the MnO6 octahedra due to theincreasing A-site disorder
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/53/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.336-338.351.pdf
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