Introduction of a tolerance factor for the Nd{sub 2}CuO{sub 4} (T{prime})-type structure
- Columbia Univ., Palisades, NY (United States)
A tolerance factor, tf = [3{radical}2r{sub o} + 2{radical}6(r{sub A} + r{sub o})]/9(r{sub B} + r{sub o}), has been established for the Nd{sub 2}CuO{sub 4}-type structure, where r{sub A}, r{sub B}, and r{sub o} are the radii of the A,B, and O ions, respectively. It is based on the geometrical matching between the A-O, B-O, and O-O bond distances, and it can be used to distinguish between Nd{sub 2}CuO{sub 4}(T{prime}-), T{sup *-}, and K{sub 2}NiF{sub 4}(T)-type phases. Using Shannon`s ionic radii, it is found that the T{prime} phases occur for tf < 1.00 while T phases form for tf > 1.00. As expected the stability boundaries of these two structure types. The fact that T{prime} and T separate at tf = 1.00 suggests that the new tolerance factor model is applicable to both structure types.
- OSTI ID:
- 450703
- Journal Information:
- Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 1 Vol. 125; ISSN 0022-4596; ISSN JSSCBI
- Country of Publication:
- United States
- Language:
- English
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