Vibrational and luminescence studies of MIIn(MoO4)2 (MI = K, Rb) and MIAl(MoO4)2 (MI = K, Na) molybdates doped with chromium(III) prepared via the Pechini method

KAl(MoO4)2, NaAl(MoO4)2, KIn(MoO4)2 and RbIn(MoO4)2 doped with 2% of chromium(III) ions have been prepared by the Pechini method. The grains of the obtained samples ranged from about 50 to a few hundreds of nm. Raman and IR studies showed that vibrational properties have been modified in comparison with the bulk material. The luminescence revealed that the prepared materials have similar properties as the bulk samples. However, the prepared samples are characterized by weaker electron–phonon coupling, in comparison with the bulk materials.