Transport and magnetic properties of the compounds YbNi4In and YbNiIn4 with valence-unstable Yb

The electrical resistance, thermal emf, and magnetic susceptibility of the compounds YbNi4In and YbNiIn4, with valence-unstable Yb, are measured at te mperatures of 4.2-300 K. The valence state of Yb is identified by measuring the x-ray L-III absorption spectra at T=300 K. YbNi4In is shown to have a Kondo magnetic lattice and exhibit crystal-field effects. The preferred sch eme is splitting of the 4f level of Yb3+ with doublet formation in the grou nd and first excited states. In the case of YbNiIn4, a valence-unstable sta te of Yb is formed that makes no significant additional contributions to th e transport coefficients. (C) 1999 American Institute of Physics. [S1063-78 34(99)00211-7].