BARC/PUB/2017/0640

 
 

Pressure induced effects on the chemical and magnetic structure of spinel MnV2O4

 
     
 
Author(s)

Singh, R.; Hansen, T.; Ritter, C.; Sharma, N.; Shahi, P.; Chatterjee, S.; Das, A.
(SSPD)

Source

Journal of Physics-Condensed Matter, 2017. Vol. 29 (34): pp. 1-6: Article no. 345802

ABSTRACT

The influence of external pressure (P ⩽ 5 GPa) on both the structural and magnetic ordering in MnV2O4 has been investigated using neutron diffraction technique. The volume and the V–V distance decrease with pressure while the c/a ratio increases, suggesting a lowering of the distortion with pressure. Under ambient conditions this compound exhibits a structural transition (TS) from tetragonal to cubic at ~53 K and a magnetic transition (TN) at ~56 K. It is found that with an increase in pressure to 5 GPa, TN increases (from 56 K to 80 K), dTN/ dP > 0, while TS decreases (from 53 K to 37 K). The non collinear magnetic structure in the tetragonal phase at 5 GPa and 10 K remains the same as at ambient pressure. However, the Mn and V sublattice, now exhibits distinct transition temperatures, TMn N ~ 80 K, and TV N ~ 60 K. The transition to the cubic phase at TS is accompanied by a collinear alignment of the Mn and V spins and a reduction in the Mn moment. The region in which the structure remains in the cubic phase with collinear magnetic structure increases with pressure from ~3 K at ambient pressure to ~43 K at 5 GPa pressure.

 
 
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