51V and 25Mg NMR Study of the Kagome Staircase Compound Mg3V2O8

Resumo

The ⁵¹V and ²⁵Mg nuclear magnetic resonance (NMR) spectra have been obtained and magnetic susceptibility has been measured in polycrystalline Mg₃V₂O₈. The analysis of ⁵¹V NMR spectra has shown that the line shift, δ(⁵¹V) = − 555 ppm, does not depend on temperature. It has been established that vanadium ions V⁵⁺ have a zero magnetic moment in this structure. The ²⁵Mg NMR spectrum consists of two lines corresponding to two crystallographically nonequivalent positions of magnesium ions in the Kagome structure: Mg(1) are « spine » and Mg(2) are « cross tie » . Quadrupole frequencies and asymmetry parameters of ²⁵Mg and ⁵¹V NMR spectra have been determined. The magnetic susceptibility is turn out to be zero (within the error) and remains constant over at a whole temperature range.