β Scribed by Ellner, Martin
No coin nor oath required. For personal study only.
Unit cell parameters were investigated for the palladium/platinum and the B^13^β¦B^16^ element-containing representatives of the Ni~2~In, NiAs and CdI~2~ types in the whole range of homogeneity. For phases belonging to the defect Ni~2~In type, macroscopic density was also measured to determinate the number of atoms in the unit cell. For the homologous phases Pd~2~Sn(h) and Pd~5~Pb~3~(h~2~), it has been found that the tin-containing compound shows (at the same Pd/B metal stoichiometry) a higher number of atoms in the unit cell than the lead-containing phase. The d electron concentration of the late transition metals controls predominantly the values of the axial ratio c/a: rhodium and iridium-containing representatives of the NiAs family (possessing the same B element) show a higher c/a ratio than corresponding palladium and platinum-containing phases. Comparing the quasihomologous stannides IrSn, PtSn and AuSn, the largest difference between the sum of atomic radii and the measured shortest atomic distance, Ξ__d__ = (r
~A~ + r
~B~) β d
~AβB~, is observed for IrSn and the smallest one for AuSn. Regarding this, the iridium and platinum-containing stannides possess obviously a larger charge transfer as well as a stronger bond energy than the gold containing compound.
π SIMILAR VOLUMES