The new ternary silicide Gd5CoSi2: Structural, magnetic and magnetocaloric properties

Stabilization by Si Substitution of the Pseudobinary Compound Gd2(Co3–xSix) with Magnetocaloric Properties around Room Temperature

“…The peaks of GdCo 2 and Gd 6 Co 4.85 are not distinguishable any more. The reflections of the main phase were indexed with space group Cmce and cell parameters a = 5.3748( 4), b = 9.5558 (6), and c = 7.1245(5) Å (Table These structural data are relatively close to those of La 2 Co 3 (space group Cmce, a = 4.886 (7), b = 10.34 (10), and c = 7.811(5) Å) 19 and La 2 Ni 3 (space group Cmce, a = 5.113( 8), b = 9.731 (6), and c = 7.907(5) Å) 20 suggesting that the new ternary phase may crystallize with the same type structure and whose formula could be rewritten as Gd 2 (Co 3−x Si x ) with x ≈ 0.44 assuming the overall composition of Gd 39.8 Co 51.5 Si 8.7 determined by EPMA (Table 2). Single crystal measurements presented in the next part confirm this assumption with a refined structure yielding the chemical formula of Gd 40 Co 50.6 Si 9.4 or Gd 2 (Co 3−x Si x ) with x ≈ 0.47 for an annealing temperature of 1073 K.…”

“…3 This compound orders ferromagnetically at 294 K and exhibits interesting magnetocaloric properties. 4−6 Thereafter, the Gd 5 CoSi 2 7 and Gd 3 Co 2.48 Si 1.52 8 phases were discovered. Gd 5 CoSi 2 adopts the Cr 5 B 3 -type structure, and Gd 3 Co 2.48 Si 1.52 adopts the Er 3 Ge 4 -type structure.…”

“…Thus, the system Gd–Co–Si was investigated after the discovery of the new Gd-rich phase Gd 6 Co 1.67 Si 3 as secondary phase during the synthesis of a GdCoSi sample . This compound orders ferromagnetically at 294 K and exhibits interesting magnetocaloric properties. − Thereafter, the Gd 5 CoSi 2 and Gd 3 Co 2.48 Si 1.52 phases were discovered. Gd 5 CoSi 2 adopts the Cr 5 B 3 -type structure, and Gd 3 Co 2.48 Si 1.52 adopts the Er 3 Ge 4 -type structure.…”

R2Co3-xSix (R = Pr, Nd, Sm, Gd) and R2Ni3-xSix (R = Gd-Er), new series of La2Ni3-type phases

“…Magnetocaloric materials which exhibit a second order ferromagnetic transition around the target application temperature are of great interest due to the easily reversible transition with little to no hysteresis, and the speed of the purely magnetic transition. To this end, significant work has been focused on the Gd-Co-Si system due to the high number of ferromagnetic phases with high transition temperatures that can be found therein [11][12][13][14][15]. During our study of this ternary system a new pseudo binary phase with the general formula Gd2(Co3-xSix) has been discovered and its structural and magnetic properties investigated [11].…”

Magnetic properties and magnetocaloric effects in GdCo9Si2 compound with multiple magnetic phase transitions

“…This point is clearly seen from the high saturated moment of Co-deficient compounds, such as Gd 5 CoSi 2 . 6 The compound shows a ferromagnetic ordering at 168 K and has large MCE with adiabatic temperature change DT ad ¼ 5.9 K and magnetic entropy change ÀDS M ¼ 8. They have gained more attention as potential highly efficient magnetocaloric materials and giant isotropic magnetostriction materials.…”