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The crystal structure, magnetic properties and magnetocaloric performances of rare earth rich RE11Co4In9 (RE = Gd, Dy and Ho) intermetallic compounds are investigated systematically in this work. All compounds in this system crystallize in the orthorhombic Nd11Pd4In9-type structure with the Cmmm space group. The stacks of alternate RE and Co/In atomic layers with z = 0, 1 and z = 1/2 along the z-axis constitute the crystal structure. These compounds belong to the REx+yM2yXx family with x = 9 and y = 2, and the ratio of the AlB2-type and CsCl-type fragments in a unit cell is y : x, i.e. 2 : 9. The characteristic of multiple magnetic phase transition is revealed with a low magnetic flux density μ0H of 0.1 T for the present compounds. The ferromagnetic (FM) to paramagnetic (PM) phase transitions of the present compounds around their respective Curie temperatures (TC) are all second order phase transitions (SOPTs). Around the TC of 86, 37 and 20 K for Gd11Co4In9, Dy11Co4In9, and Ho11Co4In9 with a magnetic flux density change Δμ0H of 0–7 T, the values of the maximum magnetic entropy change (−ΔS maxM) and temperature averaged entropy change (TEC) with 3 K span are 10.95 and 10.93 J kg−1 K−1 for Gd11Co4In9, 4.66 and 4.64 J kg−1 K−1 for Dy11Co4In9, and 12.29 and 12.09 J kg−1 K−1 for Ho11Co4In9, respectively. The corresponding values of relative cooling power (RCP) and refrigerant capacity (RC) are 538.1 and 405.9 J kg−1 for Gd11Co4In9, 213.9 and 165.9 J kg−1 for Dy11Co4In9, and 475.2 and 357.4 J kg−1 for Ho11Co4In9, respectively. [ABSTRACT FROM AUTHOR]

The crystal structures, magnetic properties and magneto-caloric effects (MCEs) of RE2Ni2In (RE = Pr, Nd, Dy and Ho) compounds were investigated. The results indicate that Pr2Ni2In and Nd2Ni2In compounds have a tetragonal Mo2FeB2-type structure belonging to the P4/mbm space group and undergo a second-order paramagnetic to ferromagnetic (PM to FM) transition at a Curie temperature (TC) of 7.5 and 10.5 K, respectively, whereas Dy2Ni2In and Ho2Ni2In compounds have an orthorhombic Mn2AlB2-type structure belonging to the space group Cmmm and possess a magnetic transition from PM to antiferromagnetic (AFM) at a Néel temperature TN of 19 and 10.5 K together with a first-order field induced metamagnetic transition, respectively. Moreover, an additional magnetic transition at a lower temperature of around 5.5 K is detected for the Ho2Ni2In compound. A considerable reversible magneto-caloric effect is observed accompanying the magnetic phase transition, and the maximum values of the magnetic entropy change (−ΔS maxM) of the present RE2Ni2In series compounds are determined to be 9.3, 11.5, 6.4 and 11.5 J kg−1 K−1 with a magnetic field change (ΔH) of up to 0–5 T for RE = Pr, Nd, Dy and Ho, respectively. [ABSTRACT FROM AUTHOR]

The crystal structure, magnetic properties and magnetocaloric effect (MCE) in A Gd(MoO 4) 2 compounds with A = Li, Na and K were investigated in detail. The X-ray diffraction (XRD) results suggest that all the A Gd(MoO 4) 2 compounds are single phased. The LiGd(MoO 4) 2 and NaGd(MoO 4) 2 crystallize in the tetragonal structure, whereas the KGd(MoO 4) 2 crystallizes in a triclinic structure. All compounds are composed of numerous irregular small particles and the corresponding constituent elements are distributed uniformly. Additionally, all compounds exhibit pronounced MCE at cryogenic temperatures. The maximum magnetic entropy change − Δ S M max values of the A Gd(MoO 4) 2 series compounds reach 33.6, 36.4 and 32.4 J/kg K @ 2.5 K with the Δ H of 0–7 T for A = Li, Na and K, respectively. [ABSTRACT FROM AUTHOR]

The magnetocaloric effect (MCE) and critical behavior in the RE PtMg (RE = Tb, Dy and Ho) intermetallic compounds around Curie temperatures T C were investigated by magnetization measurements. All the RE PtMg compounds exhibit pronounced MCE performance with the maximum magnetic entropy change (− Δ S M max ) values up to 5.1, 7.2, 10.2 J/kg K under the magnetic field change (Δ H) of 0–5 T around T C of 58, 29, and 20 K for RE = Tb, Dy and Ho, respectively. The reasonable and accurate critical exponents for the present RE PtMg series compounds for RE = Tb, Dy and Ho obtained by the Δ H dependence of Δ S M method are evaluated to be β = 0.4691, 0.4681, 0.4141, γ = 1.0412, 1.0482, 1.1067 and δ = 3.2196, 3.2393, 3.6728 around T C , which are verified by the Widom scaling law and scaling equations, respectively. • The magnetocaloric property in RE PtMg (RE = Tb, Dy and Ho) was studied. • A considerable reversible MCE was observed for all compounds. • The critical behavior in RE PtMg (RE = Tb, Dy and Ho) were studied. • The obtained critical exponents obey the Mean-field model. [ABSTRACT FROM AUTHOR]

The layer-like RE 11 Ni 4 In 9 (RE = Gd, Dy and Ho) intermetallic compounds were successfully fabricated and systematically investigated concerning crystal structure, magnetic phase transitions and magnetocaloric effect (MCE). The RE 11 Ni 4 In 9 compounds crystallize in layer-like orthorhombic crystal structure (Cmmm space group) which is composed of CsCl-type and AlB 2 -type units with the ratio of 9 : 2. The RE 11 Ni 4 In 9 compounds present multiple magnetic phase transitions at low temperature. Except for the phase transition at low temperature region, the major phase transitions of the present series compounds are of second-ordered phase transitions (SOPTs). Around the magnetic phase transition temperatures at 91, 18 and 13.5 K for Gd 11 Ni 4 In 9 , Dy 11 Ni 4 In 9 and Ho 11 Ni 4 In 9 compounds, the values of peak magnetic entropy change (− Δ S M max) with magnetic flux density change Δ H = 0–7 T and the temperature averaged magnetic entropy change with 3 K lift are 3.58 and 3.55 J/kg-K, 6.02 and 5.94 J/kg-K, as well as 12.44 and 12.25 J/kg-K for Gd 11 Ni 4 In 9 , Dy 11 Ni 4 In 9 and Ho 11 Ni 4 In 9 compounds, respectively. The corresponding relative cooling power (refrigerant capacity) values are 269.0 (206.4), 194.9 (144.7), and 353.0 (269.2) J/kg, respectively. • The RE 11 Ni 4 In 9 (RE = Gd, Dy and Ho) intermetallic compounds are fabricated. • Magnetic properties and MCE in RE 11 Ni 4 In 9 amorphous ribbon were studied. • Considerable MCE parameters were observed at low temperature. [ABSTRACT FROM AUTHOR]

Magnetocaloric effect (MCE) is a thermodynamic response of the coupling effect between the magnetic sub-lattice(s) with applied magnetic fields, which is strongly correlated with the corresponding magnetic transition. In this work, the magnetic properties, magnetic phase transition, MCE and critical behavior of the paramagnetic (PM) to ferromagnetic (FM) transition in double perovskite RE 2 CrMnO 6 (RE = La, Pr, and Nd) compounds are investigated. The double perovskite compounds reveal a second-ordered magnetic phase transition around T C of 112, 93, and 80 K for RE of La, Pr, and Nd, respectively. The corresponding values of peak magnetic entropy change (- ΔS M max) around T C are 1.31, 1.86, and 2.23 J kg−1K−1 under the ΔH of 0–7 T. Moreover, the critical exponent study was conducted to probe the nature of critical behavior around the PM to FM transition by the modified Arrott plot (MAP), Kouvel-Fisher (K–F), ΔH dependence of - ΔS M max, and universal scaling hypothesis methods. The evaluated reliable critical exponents (β, γ, and δ) data for RE 2 CrMnO 6 (RE = La, Pr, and Nd) follows the mean-field theory model, proving the existence of long-range FM orders in these double-perovskite oxide compounds. [ABSTRACT FROM AUTHOR]

• The quaternary RE Cr 2 Si 2 C (RE = Gd, Tb, Dy) compounds are fabricated. • The structural, magnetic, MTP and MC properties in RE Cr 2 Si 2 C were studied. • The GdCr 2 Si 2 C compound is considerable for cryogenic magnetic refrigeration. The rare earths (RE) based materials with large reversible magnetocaloric effects have been recently recognized as good candidates for practical cryogenic magnetic refrigeration. In this work, three RE -based quaternary silicon carbides of RE Cr 2 Si 2 C (RE = Gd, Tb, Dy) were synthesized and determined the crystal structure, magnetic properties, magnetic phase transition, and magnetocaloric performances. All RE Cr 2 Si 2 C compounds are crystallized in the carbon-filled CeMg 2 Si 2 -type crystal structure and revealed a second-order magnetic phase transition from ferromagnetic to paramagnetic without noticeable field or thermal hysteresis around the Curie temperatures (~10.9 K for GdCr 2 Si 2 C, ~16.6 K for TbCr 2 Si 2 C, and ~10.7 K for DyCr 2 Si 2 C). The magnetocaloric parameters including the maximum magnetic entropy change, temperature-averaged entropy changes with 3 K lift, as well as refrigerant capacity/relative cooling power are applied to determine the magnetocaloric performances, and the evaluated values are 21.7, 14.6 and 9.8 J/kgK, 20.97, 14.51, and 9.73 J/kgK, as well as 248.3/328.8, 302.8/393.8, and 211.3/274.9 J/kg for GdCr 2 Si 2 C, TbCr 2 Si 2 C, and DyCr 2 Si 2 C under the field change of 0–50 kOe. These results indicate that the GdCr 2 Si 2 C possesses promising magnetocaloric performances and is considerable for cryogenic magnetic refrigeration application. [ABSTRACT FROM AUTHOR]