The Investigation of the Temperature Dependence of the NMR Spectrum of ⁵¹V in DyVO₄ by Study of its Electric Quadrupole Interaction Induced Angular Variation at T=77ºK and T=292ºK

Abstract

<p>The nuclear magnetic resonance spectrum of the ⁵¹V nucleus in DyVO₄ has been investigated in order to determine if the crystal undergoes any crystallographic distortion or symmetry reduction down to liquid nitrogen temperature, T=77ºK. It has been found, using the effects of the electric quadrupole interaction at the vanadium nucleus, that no such distortion or symmetry alteration could be detected down to T=77ºK. Although it is known that the crystal undergoes a spontaneous second-order crystallographic phase transition, via the cooperative Jahn-Teller effect to a state of lower symmetry at a temperature TD=14ºK and that it undergoes a second transition to an antiferro-magnetic state at TN=3.04ºK, these phenomena were unfortunately unable to be observed due to technical difficulties. However, the existence and effects of the electric quadrupole interaction in DyVO₄ at T=77ºK and T=292ºK have been established, and speculation has been made as to the possible findings in the very low temperature range between 2ºK and 15ºK.</p>