12-15 July 2011
Saint George Hotel
Africa/Johannesburg timezone

Crystalline Electric Field Effects in PrNiGe<sub>2</sub>

13 Jul 2011, 17:00


Poster Presentation Track A - Condensed Matter Physics and Material Science Poster1


Mr Jasper Snyman Snyman (University of Johannesburg)


Within the confines of the standard model of rare earth magnetism, the high temperature magnetic properties of rare earth ions in a crystalline environment are identical to the magnetic behaviour of free tri-positive rare earth ions. At low temperatures deviations from free-ion behaviour occur due to the action of an anisotropic crystalline electric field (CEF). For Pr3+-ions in a low symmetry crystalline environment it is expected that the 9-fold degeneracy of the spin orbit coupled ground state multiplet associated with the free tri-positive ion should be completely uplifted by the CEF yielding a non-magnetic singlet ground state for the Pr3+ 4f-electrons. PrNiGe2 is known to order ferromagnetically despite the fact that the Pr3+ ions occupy the low-symmetry m2m sites in the CeNiSi2-type structure. This has prompted the current study into the ground state properties of PrNiGe2. The structure of the CEF-split energy levels in this system could be determined from specific heat measurements. The analyses point to the formation of a pseudo-doublet ground state in the system, and we forward a conceptual explanation of the observed magnetic order in PrNiGe2 in terms a fortuitous merging of electronic singlet levels into a local level dispensation of higher degeneracy.

Would you like to <br> submit a short paper <br> for the Conference <br> Proceedings (Yes / No)? Yes
Level (Hons, MSc, <br> &nbsp; PhD, other)? PhD
Consider for a student <br> &nbsp; award (Yes / No)? Yes

Primary author

Mr Jasper Snyman Snyman (University of Johannesburg)


Prof. Andre Strydom (University of Johannesburg)

Presentation Materials