, are grateful to ANR (REDIVALAN ANR-15-CE29-0019-02 and SCOSIMLIGHT ANR-13-BS07-0022-01) for the financial support to acquire the cryostat set-up. G.F.G. gratefully acknowledges the European Commission through the ERCAdG 267746 MolNanoMas (Project 267746) for financial support, Keywords: Dysprosium ? Luminescence ? Single Molecule Magnet ? Supramolecular chemistry ? Crystal field

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