skip to main content

Title: Analysis of the crystal-field spectra of the actinide tetrafluorides. II. AmF[sub 4], CmF[sub 4], Cm[sup 4+]:CeF[sub 4], and Bk[sup 4+]:CeF[sub 4]

We report a systematic analysis of the crystal-field spectra of four fluoride compounds containing tetravalent actinide ions. The first part of this work [J. Chem. Phys. [bold 95], 7194 (1991)] provided interpretation of the absorption spectra of UF[sub 4], NpF[sub 4], and PuF[sub 4]. To extend our analysis to heavier elements of the series, low-temperature absorption spectra of AmF[sub 4] and CmF[sub 4], and site selective laser-induced emission and excitation spectra of Cm[sup 4+]:CeF[sub 4] and Bk[sup 4+]:CeF[sub 4] were obtained. A model energy level calculation was found to be in good agreement with the experimental results. It is shown that the crystal-field interaction in combination with spin--orbital coupling results in significant [ital J] mixing in the excited states, but ground state wave functions are still relatively pure in [ital J] character for the tetravalent actinide ions Am[sup 4+], Cm[sup 4+], and Bk[sup 4+]. Trends in the parameters of the effective operator Hamiltonian are compared with those of a Hartree--Fock free-ion model. Interpretation of the ground-state splitting of the nominal [ital S]-state ion Bk[sup 4+] in CeF[sub 4] and color center formation in AmF[sub 4] are also discussed.
Authors:
; ; ;  [1]
  1. (Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States))
Publication Date:
OSTI Identifier:
6841563
DOE Contract Number:
W-31109-ENG-38
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; (United States); Journal Volume: 101:10
Research Org:
Argonne National Laboratory (ANL), Argonne, IL
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AMERICIUM FLUORIDES; CRYSTAL FIELD; CERIUM FLUORIDES; CURIUM FLUORIDES; BERKELIUM IONS; COLOR CENTERS; CURIUM IONS; DOPED MATERIALS; ENERGY LEVELS; EXCITED STATES; FREQUENCY MIXING; GROUND STATES; HAMILTONIANS; ION IMPLANTATION; L-S COUPLING; MATHEMATICAL MODELS; WAVE FUNCTIONS; ACTINIDE COMPOUNDS; AMERICIUM COMPOUNDS; CERIUM COMPOUNDS; CHARGED PARTICLES; COUPLING; CRYSTAL DEFECTS; CRYSTAL STRUCTURE; CURIUM COMPOUNDS; FLUORIDES; FLUORINE COMPOUNDS; FUNCTIONS; HALIDES; HALOGEN COMPOUNDS; INTERMEDIATE COUPLING; IONS; MATERIALS; MATHEMATICAL OPERATORS; POINT DEFECTS; QUANTUM OPERATORS; RARE EARTH COMPOUNDS; TRANSPLUTONIUM COMPOUNDS; TRANSURANIUM COMPOUNDS; VACANCIES 360606* -- Other Materials-- Physical Properties-- (1992-)