SPECTROSCOPIC STUDIES ON CU(II) BEARING LINARITE, CUPBSO4,(OH)(2)

The results of EPR and optical absorption spectral studies on linarite are reported here. The observed absorption bands in the optical spect rum at 12050, 16660 and 21730 cm(-1) indicate the presence of Cu(II) i on in tetragonally distorted octahedral site symmetry (4-D-4h). The pa rameters evaluated from the optical spectrum are Dq = 1205, Ds = 3763 and Dt = 1335 cm(-1) which confirm the square field coordination for C u(II) in the complex. By correlating EPR and optical data, the orbital reduction factors K-parallel to and K-perpendicular to are calculated as 0.6554 and 0.8730 respectively, and the covalency parameters are a lso calculated, in order to predict the nature of in-plane sigma-bondi ng and pi-bonding. The infrared spectrum of linarite confirms the pres ence of water and sulphate ions in the complex.