Calculation of the optical absorption spectrum of ErCl3 in poly(ethylene oxide) (PEO)

✍ Scribed by D. Brandell; M. Klintenberg; A. Aabloo; J. O. Thomas

• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 293 KB
• Volume: 80
• Category: Article
• ISSN: 0020-7608
• DOI: 10.1002/1097-461x(2000)80:4/5<799::aid-qua27>3.0.co;2-r

✦ Synopsis

The optical absorption spectrum for the rare-earth ion Er 3+ in an amorphous polymer host poly(ethylene oxide) (PEO) has been calculated. A modified Judd-Ofelt theory has been exploited to calculate the oscillator strengths for the electric-dipole transitions within the 4 f 11 configuration. Such transitions are allowed due to the admixing of opposite-parity states via the crystal field. Pertubation theory has been used to calculate the Stark level energies and the corresponding eigenstates using Racah algebra formalism. A simulated spectrum has then been constructed for this model system following molecular dynamics simulation generation of a sequence of physically representative environments for the rare-earth ions. These environments are then used to derive the crystal-field parameters needed to calculate spectral intensities and Stark energies. Molecular dynamics has also been used to probe such structurally interesting features as ion pairing, crystallization phenomena, coordination to the rare-earth ion, and radial distribution functions. Distinct qualitative trends were seen in the form of the spectral peaks for the different local Er 3+ environments.