The nature of charge ordering in rare earth manganates and its strong dependence on the size of the A-site cations

Charge ordering in rare earth manganates of the type Ln(0.5)A(0.5)MnO(3) (Ln = rare earth, A = alkaline earth) is highly sensitive to the average radius of the A-site cations, [r(A)]. Tn the small [r(A)] regime (e.g., Y0.5Ca0.5MnO3), charge ordering occurs in the paramagnetic state, the transformation to an antiferromagnetic state occurring at still lower temperatures. At moderate [r(A)] values (e.g., Nd0.5Sr0.5MnO3), a ferromagnetic metallic state transforms to a charge-ordered antiferromagnetic state with cooling. These two distinct types of charge ordering and associated properties are explained in terms of the variation of the exchange couplings J(FM) and J(AFM) with [r(A)] and the invariance of the single-ion Jahn-Teller energy with [r(A)]. A qualitative temperature-[r(A)] phase diagram, consistent with the experimental observations, has been constructed to describe the properties of the manganates in the different [r(A)] regimes. (C) 1997 Academic Press.

The Indiana State Board of Health bulletin.

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Report from committee on county reorganization as submitted to the Wayne County Board of Supervisors on October 20, 1942. Resolutions adopted on October 30, 1942.

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Manual of the Board of Education.

Description based on: 1923-1924.

Annual report of the Board of Harbor Commissioners of the City of Los Angeles, California.

Quarto size: 1954/55.

Bulletin - Virginia. State Board of Education.

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Report ... of Workmen's Compensation Board of Nova Scotia.

Description based on: 1960.

Biennial report of the State Board of Control.

1912/14-1918/20 include also Fourth to Seventh biennial report of the Board of Managers Washington State Reformatory, 1912/14-1918/20, respectively.

A State Board of Education for Illinois; the report.

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Annual report of the State Board of Health of New York.

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Address to the Board of aldermen of the city of Boston, Jan. 3, 1829, on taking final leave of the office of mayor.

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The tactics of Aelian, comprising the military system of the Grecians; illustrated with notes, explanatory plates, &c. &c. &c.

The tactics of Aelian.--Extract from the general history of Polybius.--The principal historians ancient and modern, considered in a military point of view.

Biennial report of the State Board of Control

1912/14-1918/20 include also Fourth to Seventh biennial report of the Board of Managers Washington State Reformatory, 1912/14-1918/20, respectively