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A magnetic phase diagram for EuPdSn_2 is constructed based on magnetization, DC-susceptibility and specific heat as a function of applied field, and neutron diffraction results at zero field. The contribution of the ferromagnetic FM and antiferromagnetic AFM components to the measured magnetic susceptibility can be separated and weighted as a function of the applied field B by taking the temperature dependence of the neutron counts from the FM phase at B=0 as a reference. In the magnetically ordered phase, the temperature dependence of the specific heat does not follow the mean-field prediction for the Eu^{2+} J=7/2 quantum number rather that for J=5/2. This deviation and the consequent discrepancy for the entropy is discussed in the context of a non-Zeeman distribution of the eight fold ground state. Comparing the respective variations of magnetization M(T,B) and entropy S(T,B), the thermodynamic relationship dM/dT=dS/dB=0 is observed for the ranges: 0

Gd2GaSbO7 and Gd2InSbO7 pyrochlore compounds exhibit quantum fluctuations in a spin ice-like state. These compounds have not been adequately studied based on the concept of magnetic frustration. Here, we have synthesised and characterised Gd2GaSbO7 and Gd2InSbO7 to investigate their ground-state magnetic properties. We confirmed the cubic pyrochlore structure via X-ray powder diffraction. Magnetic and heat capacity measurements show an absence of magnetic order down to 400 mK. Interestingly, the low-temperature magnetic heat capacity of Gd2GaSbO7 and Gd2InSbO7 exhibits a broad maximum around T_{\text{max}} = 0.9 K and T_{\text{max}} = 1 K, respectively. The low-temperature Cmag data fit with the power-law C_{\text{mag}} \approx T^{\frac{d}{n}} with dependencies of T^{1.71} for Gd2GaSbO7 and T^{1.49} for Gd2InSbO7, suggesting spin fluctuations caused by the disorder of magnetic moments at low temperatures. Both compounds retain residual entropy akin to water ice, resembling the spin ice state. Additionally, we analysed the ratio between nearest-neighbour exchange and dipolar interaction for all reported Gd-based pyrochlores, finding that Gd2InSbO7 has the lowest and weakest exchange interaction among them. This indicates that chemical pressure affects exchange interaction due to the different pathways of mediators between magnetic ions. This study reveals robust quantum fluctuations in the ground state in GGSO and GISO, similar to quantum spin ice compounds such as Pr2Zr2O7, Pr2Sn2O7, and Yb2GaSbO7. Other Gd-pyrochlore compounds exhibit long-range magnetic order, which is in stark contrast to this., Comment: NIL

We report on crystal structure, magnetic and thermal physical properties of EuPd$_2$Sn$_4$ stannide. From the magnetic susceptibility measurements a divalent state of Eu rare earth element was determined together with an antiferromagnetic (AFM) order at 11 K. By applying magnetic field, the magnetic behavior variation reveals a complex magnetic structure. Above a critical field Bc a ferromagnetic (FM)-like character starts to prevail. AFM and FM regimes are separated by a metamagnetic region. Heat capacity measurements confirm this behavior.

Magnetization and heat capacity measurements of ternary rare earth intermetallic compound GdNiAl3 demonstrate para to ferromagnetic transition at Tc=165.5K. In addition multiple short range magnetic transitions observed below Tc are suggestive of competing interactions in this compound. As a result of this a weak Griffiths phase type behaviour is observed in the paramagnetic region. This complex behaviour is rather supported by the random orientation of Ni centered tricapped trigonal prisms with additional Al atoms in the structure. Heat capacity and resistivity data display an interesting peak at 72 K, which is highly unaffected by magnetic fields up to 90KOe.