We studied kagome-like magnets, SrVxGa12xO19 with V3+ 3d2 in the triply degenerate t2g states, as a geometrically frustrated spin system with orbital degrees of freedom. We observed a suppression of lowtemperature spin entropy and an anomalous contraction of the V triangles on the kagome lattice, which can be regarded as the V trimerization with spin-singlet formation. This result, which is in clear contrast to their Cr3+ 3d3 analogs exhibiting a spin-liquid behavior, indicates a substantial impact of orbitals on geometricallyfrustrated magnets.
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