I will review our recent activity on minerals comprising a kagome arrangement of spin-1/2 ions (kapellasite, haydeeite and volborthite). Based on density functional theory calculations, we evaluate relevant orbitals and couplings, and provide estimates for the magnetic exchange integrals. The resulting microscopic magnetic models are challenged with exact diagonalization studies and subsequently compared to the experimental findings. We demonstrate that the correct treatment of structural peculiarities reveals unexpected relevant couplings as well as the orbital ordering, crucial for magnetism. In conclusion, the applied microscopic approach is an appropriate tool to extend our understanding about the "structure-property" relation of spin-1/2 kagome materials.
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