Configuration-selective spectroscopic studies of Er[sup 3+] centers in ErSc[sub 2]N@C[sub 80] and Er[sub 2]ScN@C[sub 80] fullerenes (original) (raw)

Low temperature photoluminescence ͑PL͒ and photoluminescence excitation ͑PLE͒ spectroscopy of high purity ErSc 2 N@C 80 and Er 2 ScN@C 80 fullerenes reveal at least two metastable configurations of the Er 3+ ion within the cage, consistent with previous observations from x-ray diffraction. Using PLE measurements at a number of different emission wavelengths we have characterized the ground state, 4 I 15/2 , and the first excited state, 4 I 13/2 , of the various Er 3+ configurations and their crystal-field splitting. We present detailed energy level diagrams for the ground and excited states of the two dominant configurations of ErSc 2 N@C 80 and Er 2 ScN@C 80 .