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arXiv · 1208.6459

Doping-induced spin-manipulation in complex trimer system Ca$_{3}$Cu$_{3}$(PO$_{4}$)$_{4}$: A First Principles Study

Debjani Karmakar·Alexander Yaresko
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Abstract

Spin-manipulated doping with magnetic (Ni) and non-magnetic (Mg) dopants constitutes the experimental attempts to obtain a singlet ground state system from the linear chain Heisenberg antiferromagnetic Cu-based $d^{9}$ spin-1/2 trimer compound Ca$_{3}$Cu$_{3}$(PO$_{4}$)$_{4}$ with doublet ground state. The present study is a first-principles based investigation of the effects of such doping on the spin-exchange mechanism and electronic structure of the parent compound. Site-selective doping with zero-spin dopants like Mg is proved to be more efficient than an integral spin dopant Ni in obtaining a spin-gap system with singlet ground state, as also observed in the experimental studies. Doping induced dimerized state is found to be the lowest in ground-state energy. Calculated spin exchange values along various possible paths resemble nicely with earlier experimental results.

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Debjani Karmakar, Alexander Yaresko. 2012-08-31. Doping-induced spin-manipulation in complex trimer system Ca$_{3}$Cu$_{3}$(PO$_{4}$)$_{4}$: A First Principles Study. https://doi.org/10.1016/j.jpcs.2013.07.011

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