Volume effect in magnetic properties of the YCo4Si compound

Electronic structure and magnetic properties of RCo5−xMx (R=Y, Pr and M=Al, Si) system

“…The SPR-KKR calculated magnetic moments are presented in Table 1, where the corresponding experimental results recorded at low temperatures are listed for comparison. As it was mentioned by earlier studies [5,11], the Curie temperature and the saturation magnetization reduction are much larger for YCo 4 The increased effects of Si for Co substitution on the magnetic properties of YCo 4 Si have been investigated by Isnard et al [5]. They ascribed this effect partially (with $ 50%) to the p(Si)-d(Co) hybridization, as Si has two electrons in the outer p shell, in contrast to Al which has only one, giving rise to different sphybridized states.…”

“…The experimental measurements [5] evidence the reduction of T c and saturation magnetization by applying pressure on the YCo 4 Si sample. The lattice parameters are calculated starting from the experimental ones and a compressibility of the same order as in YCo 4 B (k $ 0.7 Mbar À 1 ) [18].…”

“…A pressure of 6.5 kbar induces a change of volume of À 0.45% and a decrease of the calculated total magnetic moment of $4.1%, whilst using 11.5 kbar pressure, the change of volume is estimated to be about À0.8% and the decrease of the total magnetic moment is $ 7.3%. The calculated d ln M S / dp= À 6 Â 10 À 3 kbar À 1 , whilst the experimental value is d ln M S / dp= À (3.070.5) Â 10 À 3 kbar À 1 at 5 K [5]. The sign of d ln M S /dp determined either by experiment or by calculations shows that YCo 4 Si is an itinerant ferromagnet.…”

“…The main objective of this work is to investigate the effect of the Si and Al substitution on the electronic band structure of RCo 5 À x M x compounds with an emphasis on the substitution influence on the Co magnetic moments magnitude and their spin and orbital contribution. The volume effect on the magnetic properties of the YCo 4 Si was also investigated theoretically, after the experimental evidence of pressure sensitivity of the magnetic properties in this compound [5].…”

Investigation of the pressure and temperature dependence of the intrinsic magnetic properties of YCo4Ge

“…The magnetization goes from 8 down to 3.95 m B /formula unit for YCo 5 and YCo 4 Ge, respectively. This germanium induced reduction of the magnetization is smaller than what has been reported on isotype YCo 4 Si whose M s is 3.01 m B /f.u at 4 K [35] but larger than for the Al or Ga containing isotype compounds which are exhibiting 4.2 m B /f.u.…”