Stacking of the square-lattice antiferromagnetic planes in Ca{sub 2}CuO{sub 2}Cl{sub 2}

Journal Article · Wed Oct 01 04:00:00 EDT 1997 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.56.8351· OSTI ID:632618

Vaknin, D; Miller, L L; Zarestky, J L ^[1]

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1. Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011 (United States)

Single-crystal neutron elastic and quasielastic scattering and magnetization studies of the spin-(1)/(2) square-lattice Heisenberg antiferromagnet Ca{sub 2}CuO{sub 2}Cl{sub 2} indicate an unusual stacking of the antiferromagnetic planes in the N{acute e}el state (T{sub N}=247{plus_minus}5K) which is different from the collinear stacking in isostructural Sr{sub 2}CuO{sub 2}Cl{sub 2}. A generalized magnetic model is presented to describe the data. Elastic scattering along the ((1)/(2)(1)/(2)l) rod is observed above T{sub N}, suggesting that the CuO{sub 2} planes, although uncoupled, maintain some degree of two-dimensional order up to a crossover temperature (T{sub co}{approx}280 K) to the isotropic Heisenberg state. No structural phase transition from the I4/mmm symmetry was observed in the temperature range 10{endash}300 K. {copyright} {ital 1997} {ital The American Physical Society}

• Research Organization: Ames National Laboratory
• DOE Contract Number: W-7405-ENG-82
• OSTI ID: 632618
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 13 Vol. 56; ISSN 0163-1829; ISSN PRBMDO
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANTIFERROMAGNETIC MATERIALS
ANTIFERROMAGNETISM
CALCIUM CHLORIDES
CALCIUM OXIDES
COPPER CHLORIDES
COPPER OXIDES
CRYSTAL-PHASE TRANSFORMATIONS
HEISENBERG MODEL
MAGNETIZATION
NEEL TEMPERATURE
NEUTRON DIFFRACTION
STACKING FAULTS