Energy levels and hypersensitivity of samarium(III) in the elpasolite Cs2NaSmCl6

• Published in: Journal of physics. Condensed matter Vol. 18; no. 37; pp. 8503 - 8522
• Main Authors: Faucher, Michèle D, Tanner, Peter A
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 20.09.2006; Institute of Physics
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Exact sciences and technology; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of bulk materials and thin films; Other interactions of matter with particles and radiation; Physics; Diagonalization; Energy levels; Crystal field; Multiplet state; Configuration interaction; Cesium chlorides; Sodium chlorides; Energy-level transitions; Samarium chlorides; E1-transitions; Phonon sideband; Energy-level splitting; Two-photon processes; Zero phonon process; Absorption spectra
• ISSN: 0953-8984; 1361-648X
• DOI: 10.1088/0953-8984/18/37/009

Electronic absorption spectra of neat Cs2NaSmCl6 between 300 and 10 K are reported for the spectral region between 900 and 40 000 cm(-1). Interpretation of the intricate vibronic structure enables 91 conclusive and 45 tentative Kramers doublet and quartet energy levels of the 4f(5) ion Sm(3+) in this system to be assigned. Configuration interaction assisted crystal field calculations employing the diagonalization of the combined 4f(5) and 4f(4)6p(1) matrices fit the energy levels better than the conventional 4f5 crystal field calculation. The 4f(5) calculation is more accurate, however, than for the Pr(3+) and Nd(3+) elpasolite systems, showing the greater importance of intra- rather than inter-configuration interaction for the more complex electronic structure of Sm(3+). The experimental dataset generally shows agreement with that from two-photon excitation spectroscopy and the differences are highlighted. The intensity of structure at and near the zero phonon line of the hypersensitive infrared (6H(5/2))Gamma7 - > Gamma6(6F(1/2)) absorption transition increases relative to the intensity of the vibronic sideband when z is increased in Cs2NaSm(Cl(1-z)Br(z))6. This is attributed to the introduction of electric dipole transition intensity into the pure electronic transition by lowering the site-symmetry of SmCl(6)(3-), or by the presence of SmCl5Br(3-).