Energy dependence of the outer core-level multiplet structures in atomic Mn and Mn-containing compounds

• Published in: Physical review. B, Condensed matter Condensed matter, 1993-11, Vol.48 (17), p.12425-12437
• Main Authors: HERMSMEIER, B. D, FADLEY, C. S, SINKOVIC, B, KRAUSE, M. O, JIMENEZ-MIER, J, GERARD, P, CARLSON, T. A, MANSON, S. T, BHATTACHARYA, S. K
• Format: Article
• Language: English
• Subjects: 360606 - Other Materials- Physical Properties- (1992-); 664200 - Spectra of Atoms & Molecules & their Interactions with Photons- (1992-); ALKALI METAL COMPOUNDS; ATOMIC AND MOLECULAR PHYSICS; ATOMS; BINDING ENERGY; Condensed matter: electronic structure, electrical, magnetic, and optical properties; CONFIGURATION INTERACTION; CRYSTALS; ELECTROMAGNETIC RADIATION; Electron density of states and band structure of crystalline solids; ELECTRON SPECTROSCOPY; Electron states; ELEMENTS; ENERGY; ENERGY DEPENDENCE; Exact sciences and technology; FLUIDS; FLUORIDES; FLUORINE COMPOUNDS; GASES; HALIDES; HALOGEN COMPOUNDS; IONIZING RADIATIONS; Level splitting and interactions; MANGANESE; MANGANESE COMPOUNDS; MANGANESE FLUORIDES; MANGANESE HALIDES; MATERIALS SCIENCE; METALS; Other inorganic compounds; PHOTOELECTRON SPECTROSCOPY; Physics; POTASSIUM COMPOUNDS; POTASSIUM FLUORIDES; RADIATIONS; SPECTROSCOPY; THRESHOLD ENERGY; TRANSITION ELEMENT COMPOUNDS; TRANSITION ELEMENTS; X RADIATION
• ISSN: 0163-1829; 1095-3795
• DOI: 10.1103/PhysRevB.48.12425

We consider the energy dependence of the Mn 3[ital s] and 3[ital p] multiplets from gas-phase atomic Mn and crystalline MnF[sub 2] and KMnF[sub 3] over the range from x-ray photoelectron spectroscopy (XPS) energies down to energies near threshold. First comparing atomic and solid-state spectra for these multiplets permits concluding that the splittings in the compounds MnF[sub 2], MnO, and Cd[sub 0.3]Mn[sub 0.7]Te are highly atomic in character, with no significant effects due to extra-atomic screening. Measuring the energy dependence for atomic Mn, MnF[sub 2], and KMnF[sub 3] then shows for both the 3[ital s] and 3[ital p] multiplets that there is a decrease in the intensities of the higher-binding-energy quintet states relative to those of the corresponding septet states as the excitation energy is lowered. This effect on the quintet:septet branching ratios is also found to extend to rather high energies, with the ratios at the XPS limit of [approx]1400 eV above threshold being approximately 25--30 % greater than those at [approx]200 eV above threshold. We show that this energy-dependent final-state branching ratio is not due simply to spin-dependent dipole matrix elements as derived from single-configuration Hartree-Fock calculations. We suggest that this effect is caused by the sudden-to-adiabatic transition, which at lower energies favors the exchange-stabilized septet states that are the ground states of the ions formed. However, two prior theoretical models for such sudden-to-adiabatic intensity changes [Stohr, Jaeger, and Rehr, Phys. Rev. Lett. 51, 821 (1983) and Thomas, Phys. Rev. Lett. 54, 182 (1985)] were not found to describe our results well, particularly in the extension of the effect to higher energies. We consider qualitatively a configuration-interaction model with quintet-septet interchannel coupling that may better describe these effects and form the basis for more quantitative calculations.