Superconductivity in the intermetallic compound YRhAl
  The intermetallic compound, YRhAl, has been prepared and is found to be isomorphic with RRhAl (R=Pr, Nd, Gd, Ho and Tm) compounds crystallizing in the orthorhombic TiNiSi-type structure (Space group Pnma). Heat capacity and electrical resistivity measurements in the He-3 temperature range reveal that this compound is superconducting with a transition temperature, Tc, of 0.9 K. The electronic specific heat coefficient, gamma, and the Debye temperature are found to be 6.1 mJ/mole K and 197 K, respectively. The specific heat jump at the superconducting transition temperature is found to be consistent with the BCS weak-coupling limit. This combined with the earlier observation of superconductivity in LaRhAl (Tc = 2.4 K) having a different structure than that of YRhAl, suggests that the underlying structure is not very crucial for the occurrence of superconductivity in RRhAl series of compounds. 
Darshan C. Kundaliya (TIFR, Mumbai, India and University of Maryland,   College Park, MD, USA) and S. K. Malik (TIFR, Mumbai...