Abstract
Absorption spectra measured between 0.3 and 6.7 μm are reported for , , and in single-crystal gadolinium scandium gallium garnet, , at various temperatures. Energy levels split by the crystal field are identified between 1500 and 35 000 for (4), (4), and (3). The rare-earth ions occupy sites of point-group symmetry, and chromium ions are found primarily in sites of point-group symmetry. A Hamiltonian consisting of Coulombic, spin-orbit, and crystal-field terms is diagonalized to obtain theoretical energy levels for each symmetry. Empirical crystal-field parameters were determined by fitting calculated energy levels to observed levels through a variation of the ; these were compared with a lattice-sum calculation. The rms deviations between calculated and observed levels are 1.7 for (45 levels), 4.0 for (14 levels), and 87.7 for (35 levels).
- Received 4 January 1988
DOI:https://doi.org/10.1103/PhysRevB.37.8564
©1988 American Physical Society