The compounds Yb(Cu,Ag,Au)Sb were synthesized via high frequency melting of the elements in a closed Ta-crucible. The crystal structure of the novel phases was determined from X-ray powder Rietveld refinements. Dependent on the ratio RYb/R(Cu,Ag,Au) different structure types were encountered: YbCuSb (ordered Ni2In-type, RF=0.036), YbAgSb (TiNiSi-type, RF=0.054) and YbAuSb (LiGaGe-type, RF=0.038). The results of the magnetic measurements revealed that the compounds YbCuSb and YbAgSb are temperature independent Pauli-type paramagnets whilst a small magnetic moment (≈1μB) was observed for YbAuSb. In good agreement, X-ray absorption spectroscopy (at 10 and 300 K) confirmed for all three compounds dipositive Yb with temperature independent valencies of 2.06 (M=Ag), 2.08 (Cu) and 2.14 (Au); possibly owing to small amounts (less than up to ≈4%) of Yb3+ grain boundary effects. © 1997 Elsevier Science S.A.
The crystal structure and magnetic properties of YbMSb, M=Cu, Ag, Au
SACCONE, ADRIANA;FERRO, RICCARDO
1997-01-01
Abstract
The compounds Yb(Cu,Ag,Au)Sb were synthesized via high frequency melting of the elements in a closed Ta-crucible. The crystal structure of the novel phases was determined from X-ray powder Rietveld refinements. Dependent on the ratio RYb/R(Cu,Ag,Au) different structure types were encountered: YbCuSb (ordered Ni2In-type, RF=0.036), YbAgSb (TiNiSi-type, RF=0.054) and YbAuSb (LiGaGe-type, RF=0.038). The results of the magnetic measurements revealed that the compounds YbCuSb and YbAgSb are temperature independent Pauli-type paramagnets whilst a small magnetic moment (≈1μB) was observed for YbAuSb. In good agreement, X-ray absorption spectroscopy (at 10 and 300 K) confirmed for all three compounds dipositive Yb with temperature independent valencies of 2.06 (M=Ag), 2.08 (Cu) and 2.14 (Au); possibly owing to small amounts (less than up to ≈4%) of Yb3+ grain boundary effects. © 1997 Elsevier Science S.A.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.