The behavior of the metamagnetic transition and the magnetic susceptibility maximum in the Lu(Co1-xSnx)2, Lu(Co 1-xGex)2, Lu(Co1-xSi x)2, Y(Co1-xAlx)2, Y(Co1-xGax)2 and Y(Co1-xSi x)2 compounds has been investigated. The critical magnetic field μ0Hc for the metamagnetic transition decreases with the increase of x in Lu(Co1-xSnx)2, Lu(Co1-xGex)2, Lu(Co1-xSi x)2, Y(Co1-xAlx)2 and Y(Co1-xGax)2, accompanied by a decrease of the magnetic susceptibility maximum temperature Tmax. The larger the lattice expansion, the stronger the concentration dependences of μ0Hc and Tmax in the Lu(Co 1-xSnx)2, Lu(Co1-xGe x)2 and Lu(Co1-xSix)2 systems. The exchange-enhanced Pauli paramagnetic properties are affected by the lattice expansion. The relation between the critical field of the metamagnetic transition μ0Hc and the inverse magnetic susceptibility at Tmax, χ(Tmax)-1, is fitted to a universal straight line. The onset of ferromagnetism in Y(Co 1-xGax)2 has been verified for the first time. The values of the magnetic moment Ms and the Curie temperature T C of Y(Co1-xGax)2 are smaller than those of Y(Co1-xAlx)2. On the other hand, no evidence of the onset of a ferromagnetic state is obtained in the Y(Co 1-xSix)2 compounds with 0.00 ≤ x ≤ 0.15. The ferromagnetism appears in both Lu(Co1-xMx)2 and Y(Co1-xMx)2 only when M is one of the group IIIA elements Al or Ga, implying that the p-d hybridization has a more significant effect on the onset of ferromagnetism than the lattice expansion.
ASJC Scopus subject areas