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Single crystals of Sm 3 Co 4 Sn 13 and Tb 3 Co 4 Sn 13 are synthesized using tin flux method [1]. Sm 3 Co 4 Sn 13 and Tb 3 Co 4 Sn 13 of the Yb 3 Rh 4 Sn13 type crystallize in the cubic Pm3n space group with the lattice parameters $a\sim 9.515$ A and 9.464 A. In contrast to the previous DFT calculations [2], the temperature-dependent magnetic susceptibility data show that both Sm 3 Co 4 Sn 13 and Tb 3 Co 4 Sn 13 order antiferromagnetically at $T_{\mathrm{N}}\sim 7.8$ K and 11.4 K. Temperature dependence of ZFC and FC magnetizations for Sm 3 Co 4 Sn 13 shows a weak ferromagnetic behavior at 62 K. The effective moment of the Sm and Tb analogues were determined as 0.72 μ B and 9.54 μ B which are close to the calculated effective moment of R3+ ions. The trend of AFM ordering temperatures of R 3 Co 4 Sn 13 is proportional to the de Gennes factor.

Ternary stannides R-TM-Sn (R represents rare-earth element and TM represents transition metal) with the Yb 3 Rh 4 Sn 13 -type structure continue to attract attention in condensed matter physics due to its structural, electronic, and magnetic phenomena in the materials of this family. In this work, we report the single crystal synthesis and the physical properties of Nd 3 Co 4 Sn 13 . Nd 3 Co 4 Sn 13 is an antiferromagnetic conpound with T N ∼2.5 K and the magnetism is induced by neodymium atoms rather than cobalt [1]. To shed light on the evolution of magnetic behavior, we synthesis the single crystal by Sn self-flux method which sealed the high purity neodymium, cobalt and tin with stoichiometry in vacuumed quartz tube then heated to 1050 °C and quanched at 600 °C. The crystal photograph and powder X-ray diffraction pattern are showed in Fig. 1. The temperature dependent of susceptibility of per Nd display Curie-Weiss behavior with $T_{\mathrm{N}}\sim 2.42\ \mathrm{K}$ is displayed in Fig. 2. Accroding the fitting result by Curie-Weiss law, the Curie constant as 1.66 and the effective magnetic monent $\mu_{\text{eff}}$ as $3.65\mu_{\mathrm{B}}$ close to theoretical value indicate that the magnetism in this alloy was determined by trivalent Nd atoms[2]. Besides, the electric resistant $\rho$ , Hall coeffecient $R_{\mathrm{H}}$ and 59Co nuclear magnetic resonance (NMR) were also carried out so that the Fermi-level density of state would be disscuessed in this work.

While Heusler-type Ni 2 MnGa exhibits both ferromagnetic and martensitic phase transitions at 380 K and 220 K, respectively, Ni 2 MnAl with the L2 1 structure shows only a ferromagnetic ordering near room temperatures. In this work, we alloyed both compounds with different Al/Ga ratio to study the interplay between martensitic and magnetic phase transitions of Ni 2 MnGa 1−x Al x . Results indicate that both martensitic and magnetic transition temperatures considerably increase for the low Al concentration (x 0.10), a drastic suppression of martensitic transition along with a linear decrease of magnetic ordering temperature takes place. Such observations are in contrast to the general expectation for the nonmagnetic doping. It thus points out that the effect of disorder introduced by the Al substitution should play an important role on the phase transition characteristics of these alloys.

We report a study of the superconducting rhenium-based borides Mo 7 Re 13 B and W 7 Re 13 B by means of the 11B nuclear magnetic resonance (NMR) spectroscopy. Superconducting behavior with transition temperatures of 8.3 K and 7 K for Mo 7 Re 13 B and W 7 Re 13 B respectively have been reported. In the present work, NMR results indicate that the B Fermi level density of states is not predominated by p bands and the s-character electrons are the main origin responsible for the observed Knight shift as well as the spin-lattice relaxation rate (1/T 1 ). We thus deduce the partial B 2s Fermi level density of states, N s (E F ), for both materials from 1/T 1 analysis. Universally small N s (E F ) are found in these compounds, similar to those observed in other rhenium-based superconducting borides such as Re 7 B 3 and Re 3 B.