OPTICAL AND MICROWAVE STUDY OF ND3+ IONS IN ND2O3

Raman scattering and luminescence of the Nd3+-ion crystal-field excita tions in Nd2O3 single crystal and polycrystalline powder are studied a s a function of temperature and magnetic field. Splitting of Kramers d oublets due to Nd3+-Nd3+ interactions is not observed down to T=3.8 K and no crystal-field-phonon symmetry allowed coupling is detected. How ever, microwave dielectric measurements under magnetic field indicate that a magnetic phase transition due to Nd3+-Nd3+ magnetic moment inte ractions occurs below 2 K. [S0163-1829(97)01342-8].