Investigations of the optical band positions, EPR parameters and defect structure for the trigonal Cr³⁺–Li⁺ centre in CsMgCl₃ crystal

Abstract

A unified calculation of optical band positions and electron paramagnetic resonance (EPR) (or spin-Hamiltonian) parameters for the trigonal Cr³⁺–Li⁺ centre in CsMgCl₃ crystal is made by using the complete diagonalisation (of energy matrix) method based on the two-spin–orbit-parameter model. In this model, the contributions from the spin–orbit parameter of central dⁿ ion and that of ligand ion are included. From the calculation, the 11 observed optical and EPR data (eight optical band positions and three EPR parameters g_//, g_⊥, D) are reasonably explained with five adjustable parameters and the defect structure of the Cr³⁺–Li⁺ centre (which is consistent with the expectation based on the electrostatic interaction) in CsMgCl₃ is acquired. The results are discussed.

Keywords:

• optical spectrum
• electron paramagnetic resonance
• crystal- and ligand-field theory
• defect structure
• CsMgCl₃: Cr³⁺

PACS Nos.:

• 71.70Ch
• 76.30Fc
• 71.55Ht
• 78.40Ha

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This project is supported by the Initial Foundation of Mianyang Normal University [grant number MQD2011A05]; the Key Project of Sichuan Provincial Science and Technology Department [grant number 2011SZZ029], [grant number 2012SZZ025], [grant number 2012JY0045].