ESR investigations of VO2+ doped ferroelectric tris sarcosine calcium chloride

Abstract

ESR studies of vanadyl ions doped in ferroelectric tris sarcosine calcium chloride single crystals are carried out. The room temperature spectra indicate four magnetically inequivalent complexes which become equivalent along the crystallographic axes. The z axes of two of these correspond to two Ca–O bond directions, suggesting substitutional sites for the paramagnetic ion. The molecular orbital coefficients are estimated from the ESR and optical absorption data which indicate the complex to be ionic except for the extremely low value for e*π2. A new band is observed in the optical absorption spectrum which might be due to the b2↔a transition. The equivalency at room temperature is lost at liquid nitrogen temperature.