Small nanoparticle, i.e. Group of atoms or molecules whose largest overall dimension is only a few nanometres.

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A number of atoms bound or arranged together, forming an assembly of nanoscale size. Metal nanoclusters exhibit tunable resonant behavior; semiconductor clusters show quantum-dot behavior.

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Non covalently or covalently bound group of atoms or molecules whose largest overall dimension is in the nanoscale

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Group of atoms or molecules whose largest overall dimension is typically in the range of a few nanometres

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