Accession Number : AD0627348

Title :   ENERGY TRANSFER BETWEEN EXCITED STATES OF HO(3+) IN LACL3.

Descriptive Note : Interim technical rept. no. 1,

Corporate Author : CARLYLE BARTON LAB JOHNS HOPKINS UNIV BALTIMORE MD

Personal Author(s) : Porter,John F. ,Jr.

Report Date : JAN 1966

Pagination or Media Count : 143

Abstract : The transfer of energy between excited states of Ho(3+) in LaCl3 was studied ar 4.2K. It was established that the ion pair process is responsible for the relaxation of the E level to the C level by exciting an adjacent ion from the ground state to the first excited state, Y. A similar process is responsible for the J to E relaxation but in this case the emission of a phonon is also required to conserve energy. The rise time for E fluorescence with J excitation was measured and found to be equal, within experimental error, to the J decay time. This indicates only that if there are special sites for the ion pair interaction, the transition rate for the process is comparable to the radiative rate. The temperature dependence of the decay of the 3H6 to the 3H5 in Pr(3+) as observed previously using the quantum counter technique is explained on the basis of a pair interaction. Comparisons are made with other investigations and areas of agreement or disagreement discussed.

Descriptors :   (*HOLMIUM, ATOMIC ENERGY LEVELS), (*LANTHANUM COMPOUNDS, CHLORIDES), CRYSTALS, IMPURITIES, IONS, EXCITATION, RELAXATION TIME, PHONONS, FLUORESCENCE, PROMETHIUM, STARK EFFECT

Subject Categories : Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE