Impurity model for Mn ions: Possibility of charge order and lattice distortions

Journal Article · Thu Apr 01 04:00:00 EST 1999 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.369963· OSTI ID:336637

Schlottmann, P ^[1]

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1. Department of Physics, Florida State University, Tallahassee, Florida 32306 (United States)

Mixed valent manganese ions play an important role in the magnetoresistance of LaMnO{sub 3}-based systems. We consider a Mn impurity with the Mn{sup 4+} represented by a spin S=3/2 (three localized 3d-t{sub 2g} electrons) and the Mn{sup 3+} configuration having an additional localized 3d-e{sub g} electron to form a total spin (S+1/2). The e{sub g} electron hybridizes with conduction electrons (representing the crystal), giving rise to a quadrupolar Kondo effect. The formation of the quadrupolar singlet interferes with the usual spin Kondo effect. Using the noncrossing diagram approximation, we calculate the ground state energy, valence, charge susceptibility, and the quadrupolar susceptibility as a function of the energy of the e{sub g} level for H{r_arrow}0 and compare it to results for H=0 and the ferromagnetic lattice. Both, the charge and quadrupolar susceptibilities, are larger in the spin-polarized limit, indicating that this state is more favorable for charge order and lattice distortions. {copyright} {ital 1999 American Institute of Physics.}

• OSTI ID: 336637
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 8 Vol. 85; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
FERROMAGNETIC MATERIALS
GROUND STATES
IMPURITIES
KONDO EFFECT
LANTHANUM COMPOUNDS
LANTHANUM OXIDES
LATTICE PARAMETERS
MAGNETIC SUSCEPTIBILITY
MAGNETORESISTANCE
MANGANESE IONS
MANGANESE OXIDES
VALENCE