First-principles study of the organometallic S=1/2 kagome compound Cu(1,3-bdc)

Article

关键词: SPIN LIQUIDS;    HEISENBERG-ANTIFERROMAGNET;    SUPEREXCHANGE INTERACTION;    WEAK FERROMAGNETISM;    WANNIER FUNCTIONS;    LATTICE;    SPECTRA;    EXCITATIONS;    SYSTEMS;    STATES;   

DOI  :  10.1103/PhysRevB.92.165101

来源: SCIE

【 摘 要 】

Cu(1,3-benzenedicarboxylate) [Cu(1,3-bdc)] contains structurally perfect kagome planes formed by Cu2+ ions without the presence of diamagnetic defects. This organometallic compound should serve as a precious platform to explore quantum frustrated magnetism, yet the experimental results so far are mysterious, leading to questions such as, Is Cu(1,3-bdc) just a trivial weak ferromagnet? Using the density functional theory, we have systematically studied the electronic and magnetic properties of Cu(1,3-bdc), putting forth a theoretical basis to clarify this novel material. We present numerical evidence of a dominating antiferromagnetic (AFM) exchange between nearest-neighbor (NN) Cu2+ as experimentally extracted from the high-temperature susceptibility data. We further show that beyond the NN AFM exchange, the additional interactions in Cu(1,3-bdc) have similar strength as those in the well-studied kagome antiferromagnet, herbertsmithite, by designing a comparative study. In the end, we discuss our understanding of the phase transition and FM signals observed under low temperature.

【 授权许可】

Free