Frustration-induced non-Curie-Weiss paramagnetism in La 3 Ir 3 O 11 : A fractional valence state iridate

摘要: Experimental and theoretical studies are performed on ${\mathrm{La}}_{3}{\mathrm{Ir}}_{3}{\mathrm{O}}_{11}$, an iridate hosting a $+4.33$ fractional valence state for Ir ions three-dimensional frustrated structure composed of edge-shared ${\mathrm{Ir}}_{2}{\mathrm{O}}_{10}$ dimers. These features expected to enhance intersite hoppings reduce magnetic moments ions. However, spin-orbit driven Mott insulating transport is observed, which supported by our first-principles calculations. Most importantly, geometrical frustration competing interactions result in non-Curie-Weiss paramagnetic ground state, revealing no order down 2 K. This unusual further demonstrated modeling process, suggesting possible candidate the spin-liquid state.