Selective spin-state and metal-insulator transitions in GdBaCo2O5.5

被引：42

作者：

Frontera, C

García-Muñoz, JL

Llobet, A

Mañosa, L

Aranda, MAG

机构：

[1] CSIC, Inst Ciencia Mat Barcelona, E-08193 Bellaterra, Spain

[2] CNRS, Lab Magnetisme Louis Neel, F-38042 Grenoble 9, France

[3] Univ Barcelona, Fac Fis, Dept Estructura & Constituents Mat, E-08028 Barcelona, Spain

[4] Univ Malaga, Dept Quim Inorgan Cristalog & Mineral, E-29071 Malaga, Spain

来源：

JOURNAL OF SOLID STATE CHEMISTRY | 2003年 / 171卷 / 1-2期

关键词：

D O I：

10.1016/S0022-4596(02)00232-3

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

By means of ultra-high resolution synchrotron diffraction and calorimetry measurements we have studied the metal-insulator transition in GdBaCo2O5.5. The appearance of the metallic state is attributed to a sudden excitation of some electrons in the octahedra (t(2g)(6) state) into the Co e(g) band (final t(2g)(4)e(g)(2) state). In contrast, the t(2g)(5)e(g)(1) state in the pyramids does not change at thetransition. Calorimetry measurements show that the insulator-to-metal transition is first order and the entropy change estimated from the latent heat corroborates the pictured scheme. (C) 2003 Elsevier Science (USA). All rights reserved.

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页码：349 / 352

页数：4

相关论文

共 23 条

[1] Two spin-state transitions in LaCoO3 [J].

Asai, K ;

Yoneda, A ;

Yokokura, O ;

Tranquada, JM ;

Shirane, G .

JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, 1998, 67 (01) :290-296

[2] AN INTERPRETATION OF THE MAGNETIC PROPERTIES OF THE PEROVSKITE-TYPE MIXED CRYSTALS LA1-XSRXCOO3-LAMBDA [J].

GOODENOUGH, JB .

JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS, 1958, 6 (2-3) :287-297

[3] NEUTRON-DIFFRACTION STUDY OF THE MAGNETIC PROPERTIES OF PEROVSKITE-LIKE COMPOUNDS LABO3 [J].

KOEHLER, WC ;

WOLLAN, EO .

JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS, 1957, 2 (02) :100-106

[4] Intermediate-spin state and properties of LaCoO3 [J].

Korotin, MA ;

Ezhov, SY ;

Solovyev, IV ;

Anisimov, VI ;

Khomskii, DI ;

Sawatzky, GA .

PHYSICAL REVIEW B, 1996, 54 (08) :5309-5316

[5] Thermopower in cobalt oxides [J].

Koshibae, W ;

Tsutsui, K ;

Maekawa, S .

PHYSICAL REVIEW B, 2000, 62 (11) :6869-6872

[6] Charge and orbital ordering and spin-state transition driven by structural distortion in YBaCo2O5 [J].

Kwon, SK ;

Park, JH ;

Min, BI .

PHYSICAL REVIEW B, 2000, 62 (22) :14637-14640

[7]

Larson A.C., 1994, LAUR86748

[8] Structural and magnetic studies of ordered oxygen-deficient perovskites LnBaCo2O5+δ, closely related to the "112" structure [J].

Maignan, A ;

Martin, C ;

Pelloquin, D ;

Nguyen, N ;

Raveau, B .

JOURNAL OF SOLID STATE CHEMISTRY, 1999, 142 (02) :247-260

[9] Magnetoresistance in the oxygen deficient LnBaCo(2)O(5.4) (Ln=Eu, Gd) phases [J].

Martin, C ;

Maignan, A ;

Pelloquin, D ;

Nguyen, N ;

Raveau, B .

APPLIED PHYSICS LETTERS, 1997, 71 (10) :1421-1423

[10] Metal-insulator transition induced by a spin-state transition in TbBaCo2O5+δ (δ=0.5) [J].

Moritomo, Y ;

Akimoto, T ;

Takeo, M ;

Machida, A ;

Nishibori, E ;

Takata, M ;

Sakata, M ;

Ohoyama, K ;

Nakamura, A .

PHYSICAL REVIEW B, 2000, 61 (20) :13325-13328