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Single crystal of the stoichiometric Ni2MnSn alloy (cubic L21 crystal structure) was prepared by the Czochralski method. The values of the magneto-crystalline anisotropy constant K1 have been determined at temperature 10 K under ambient and high hydrostatic pressures, K1 = + 0.17 × 104 and +1.96 × 104 J/m3 (0.7 GPa), respectively. The pressure-induced decrease of magnetization was confirmed and hence the significant non-trivial increase of uniaxial anisotropy with increasing pressure points to a possible distortion of the cubic structure of the single crystal under hydrostatic pressure. Simultaneously, the more pronounced and pressure almost insensitive magneto-crystalline anisotropy, K1 = + 9.1 × 104 J/m3, has been observed in the martensite phase (orthorhombic structure) of the off-stoichiometric Ni2Mn1.43Sn0.57 alloy. The effect of a directional dependence of the Young modulus that was theoretically derived in the case of the Ni2MnSn-based alloys is discussed. [ABSTRACT FROM AUTHOR]

The LuPd 2 Si 2 compound is a member of a large group of compounds crystallizing in the ThCr 2 Si 2 tetragonal type of structure. The negative thermal expansion of the lattice parameter c was determined by means of an x-ray diffraction experiment performed at different temperatures between 3 K and 300 K. Temperature of transition to a superconducting state was calculated and experimentally confirmed at 0.6 K. Comparison between results of theoretical calculations based on the local spin density approximation (LSDA) and the generalized gradient approximation methods (GGA) is given in the article. [ABSTRACT FROM AUTHOR]

Abstract: We present study of the anisotropic magnetocaloric effect in TbNiAl crystallizing in the hexagonal ZrNiAl-type structure. TbNiAl orders antiferromagnetically below T N =47K and undergoes second magnetic phase transition to another antiferromagnetic structure at T 1 =23K. Magnetization and specific heat measurements on single crystal revealed strongly anisotropic magnetocaloric effect. The large effect occurs for field applied along the hexagonal c-axis whereas the entropy change is almost zero for the perpendicular field direction. Plateau-like character of the determined temperature change is observed between T N and T 1. [Copyright &y& Elsevier]

Abstract: We present study of the anisotropic magnetocaloric effect in DyNiAl. This compound crystallizes in the hexagonal ZrNiAl-type structure, orders magnetically below and undergoes a further magnetic phase transition at . The Dy-moments are aligned ferromagnetically along the hexagonal -axis below , the additional antiferromagnetic component develops within the basal plane below . The magnetocaloric effect was evaluated from the magnetization measurements with field applied along the -axis and perpendicular to it. Our data reveal a strong anisotropy of the magnetocaloric effect. The large effect occurs for field applied along the -axis whereas the entropy change is small for the perpendicular field direction. [Copyright &y& Elsevier]

• Thermal expansion of Ce 2 Pd 2 In is anisotropic having opposite sign along a or c. • Ce magnetic moments and long-range order are remarkably stable in applied pressures. • Hydrostatic pressure promotes antiferromagnetism on the account of ferromagnetism. • Uniaxial pressure along c -axis has no significant effect on transition temperatures. • Two types of magnetic order in Ce 2 Pd 2 In are effectively degenerate. Among a large group of R 2 T 2 X intermetallics (R = rare earth, T = transition element, X = p -metal) crystallizing in the Shastry-Sutherland-like tetragonal structure, Ce 2 Pd 2 In represents a rare example of Ce-based ferromagnet, reached, however via an antiferromagnetic phase stable at higher temperatures. Here we describe the development of magnetism in Ce 2 Pd 2 In under external hydrostatic and uniaxial pressure, monitored by means of electrical resistivity, magnetization, and AC magnetic susceptibility experiments on a high-quality single crystal. The experiments prove a stability of the 4 f magnetism in pressures up to 3 GPa. At these pressures only slightly reduced spontaneous magnetization in the FM state and enhanced electrical resistivity with signs of Kondo lattice behavior are observed. The AFM Néel temperature (T N = 4.65 K) is essentially pressure independent, while the Curie temperature (T C = 4.16 K at ambient pressure) significantly decreases under hydrostatic pressure. The fact that the ferromagnetic phase can be re-entered in weak magnetic fields (0.05 T) proves that the two types of magnetic order are effectively degenerate. Interestingly, T C is not affected by uniaxial pressure applied along the tetragonal c- axis, T N value exhibits only a weak decrease of 0.25 K GPa−1 under such uniaxial pressure. The crystal structure of Ce 2 Pd 2 In exhibits a strongly anisotropic thermal expansion with anomalous expansion of the c -parameter with decreasing T. Modest size of magnetostriction effects, observed by dilatometry at ambient pressure, indicates only regular magnetovolume interactions. [ABSTRACT FROM AUTHOR]

We have studied the development of the magnetocaloric effect in the (Tb,Y)NiAl and TbNi(Al,In) series as determined from magnetization measurements. The transition from antiferromagnetic order in TbNiAl to ferromagnetic order in Tb0.7Y0.3NiAl is accompanied by increase of the maximum entropy change from - 4.1 to - 4.4 J kg-1 K-1. In the TbNi(Al,In) series, the change of uniaxial anisotropy in TbNiAl to the easy-plane anisotropy in TbNiIn leads to broadening of the magnetocaloric effect accompanied with large increase of the relative cooling power from 66 to 120 J kg-1. [ABSTRACT FROM AUTHOR]