TY - JOUR
T1 - S=1/2 antiferromagnetic chains and dimers on hole-doped edge-sharing CuO2 chains
AU - Hiroi, Zenji
AU - Okumura, Makoto
AU - Yamada, Takahiro
AU - Takano, Mikio
N1 - Funding Information:
This research was supported by a Grant-in-Aid for Scientific Research given by Ministry of Education, Science, Sports, and Culture, Japan, and by the CREST program (Core Research for Evolutional Science and Technology) of the Japan Science and Technology Corporation.
PY - 2001/4/12
Y1 - 2001/4/12
N2 - Holes doped on edge-sharing CuO2 chains are almost localized because of nearly orthogonal Cu-O-Cu bonds. Consequently, only spin degrees of freedom survive at low temperatures, which sometimes presents unusual quantum magnetism. Quasi-one-dimensional cupric oxides Ca1-xCuO2+δ and Sr14Cu24O41, both containing 25-50% hole-doped edge-sharing CuO2 chains, are studied by uniform magnetic susceptibility and specific heat measurements on a series of polycrystalline samples with controlled metal and oxygen contents. Most spins are always dimerized in Sr14Cu24O41, while, in contrast, antiferromagnetic chains made of nearly 50% spins exist with the remainder forming dimers of variable density in Ca1-xCuO2+δ. A two-sublattice model is proposed by considering that the nearest-neighbor couplings are negligibly small, due to both geometrical frustration and the special Cu-O-Cu bond angle of ∼95°.
AB - Holes doped on edge-sharing CuO2 chains are almost localized because of nearly orthogonal Cu-O-Cu bonds. Consequently, only spin degrees of freedom survive at low temperatures, which sometimes presents unusual quantum magnetism. Quasi-one-dimensional cupric oxides Ca1-xCuO2+δ and Sr14Cu24O41, both containing 25-50% hole-doped edge-sharing CuO2 chains, are studied by uniform magnetic susceptibility and specific heat measurements on a series of polycrystalline samples with controlled metal and oxygen contents. Most spins are always dimerized in Sr14Cu24O41, while, in contrast, antiferromagnetic chains made of nearly 50% spins exist with the remainder forming dimers of variable density in Ca1-xCuO2+δ. A two-sublattice model is proposed by considering that the nearest-neighbor couplings are negligibly small, due to both geometrical frustration and the special Cu-O-Cu bond angle of ∼95°.
KW - CuO chain
KW - Hole-doping
KW - Quantum spin system
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U2 - 10.1016/S0925-8388(00)01314-1
DO - 10.1016/S0925-8388(00)01314-1
M3 - Article
AN - SCOPUS:0035848990
VL - 317-318
SP - 164
EP - 170
JO - Journal of Alloys and Compounds
JF - Journal of Alloys and Compounds
SN - 0925-8388
ER -