Refractive index dependence of the radiative rate of a magnetic dipole transition for a nanoparticle system

The emission spectra of Cs2NaEuCl6 nanoparticles (NPs) synthesized by the hot injection method are interpreted. Dispersion of the NPs in alkane solvents experimentally enables the magnetic dipole radiative rate in vacuum for the D-5(0) -F-7(1) channel to be determined as 14.7 +/- 0.1 s(-1), in agreement with the calculated value.