An EPR study of VO2+ and Cr3+ in (NH4)2SbCl5

Single crystal X-band EPR studies of VO2+ and Cr3+ in the matrix (NH4)2SbCl5 show the impurity ions to substitute in an antimony site, a site of approximately C4v five coordinate symmetry. The vanadyl species exhibits axial symmetry with g∥=1.9478± 0.0001, g⊥=1.9793± 0.0001, A∥=0.01688± 0.00001 cm−1, A⊥=0.0062± 0.00001 cm−1, and the chromium species rhombic symmetry with gx=1.9835± 0.0002, gy=1.9839± 0.0002, gz=1.9853± 0.0001, D=0.03706± 0.00001 cm−1, E=0.00304± 0.00001 cm−1, A=0.00165± 0.00002 cm−1. Molecular orbital and ligand field calculations support the assignment of the magnetic species as VOCl42− and CrCl52−, respectively.