Valence Transition between Eu²⁺State and Eu³⁺State in Eu_xY_1-xPd₂Si₂and Eu_xLa_1-xPd₂Si₂

Magnetic Structure of Divalent Europium Compound EuGa4Studied by Single-Crystal Time-of-Flight Neutron Diffraction

“…1 Valence instability and heavy-electron state are reported in other member of isostructural EuT 2 X 2 as well. [2][3][4][5][6][7][8][9] Magnetism of Eu ions has strong and unique dependence on its valence state; a nonmagnetic state with a finite orbital momentum becomes a ground state in a trivalent case, whereas divalent Eu ions carry large spin moment without orbital contribution, J=S =7/2. Therefore EuT 2 X 2 can be expected to exhibit emergent phenomena which stems from mutual interplay among valence, spin and orbital degrees of freedom.…”

Possibility of the Kondo effect in diluted EuPd2Si2 systems with constant lattice volume

“…1 displays the normalized electrical resistivity (NR) Dr(T)/Dr(RT), where Dr(T) denotes r(T) subtracted for the residual resistivity. A characteristic peak at 170 K for x ¼ 0 relates to the valence transformation from the Eu 2+ state to the Eu 3+ with decreasing temperatures [3]. The steep decrease in NR below about 150 K is dominated by the inter-site cooperative effect on the Eu-sites.…”

“…In order to discuss this issue strictly, it is plausible to practice the dilution keeping the lattice volume, or, if possible, lattice parameters unchanged, since T V is rather sensitive to the change in them [3]. In this paper, the observations of C(T) and electrical resistivity r(T) below the room temperature (RT) for Eu-diluted alloys of (Eu 1Àx (La 0.67 Y 0.33 ) x )Pd 2 Si 2 with almost constant lattice volume and parameters are presented.…”