EPR and optical studies of vanadium doped potassium dihydrogen citrate (C6H7KO7) single crystal.

An EPR and optical studies of VO2+ doped potassium dihydrogen citrate (PDHC) single crystals have been carried out at room temperature. It crystallizes in triclinic symmetry with the unit cell dimensions: a=11.343Å, b=13.078Å, c=6.272Å, α=89.79°, β=94.36°, γ=104.2°. The angular variation of EPR spectra have shown that two different VO2+ complexes are located in different chemical environments and each environment contains one magnetically VO2+ site occupying substitutional position in the lattice and show very high angular dependence.