Optical and EPR spectra of libethenite mineral

Abstract

The optical absorption and EPR spectra of libethenite Cu₂(PO₄)(OH) of Southern Shaba, Zaire are studied. The optical absorption bands are observed at 12190, 10525 and 8545 cm⁻¹, The octahedral field parameter Dq and tetragonal field parameters Ds and Dt are found to be 1053, 1458 and 542 cm⁻¹, respectively. The EPR spectrum of the mineral contains unresolved copper hyperfine lines due to the high percentage of the paramagnetic ion and a radical presumably PO² ₄-. The orbital reduction parameters have also been calculated.

Keywords:

• Copper bearing mineral
• libethenite
• optical
• EPR spectra
• copper(II) ion
• crystal field parameters
• PO²⁻ ₄ radical