¹¹³Cd NMR-spectroscopic characterization of Y₂Cu₂Cd and Y₂Pd₂Cd

Samples of YPdCd, Y 2 Pd 2 Cd and Y 2 Cu 2 Cd were synthesized from the elements by induction melting. The three cadmium phases were characterized through their Guinier powder patterns. YPdCd crystallizes with the hexagonal ZrNiAl-type structure (space group P <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <m:mrow> <m:mover accent="true"> <m:mn>6</m:mn> <m:mo>‾</m:mo> </m:mover> </m:mrow> </m:math> 6̄ 2 m ; a = 756.0(4) and c = 384.7(2) pm). The structure of Y 2 Pd 2 Cd was refined from single-crystal X-ray diffractometer data: Mo 2 B 2 Fe type, tetragonal space group P 4/ mbm , a = 765.33(3), c = 370.30(2) pm, w R 2 = 0.0254, 289 F 2 values and 12 variables. Y 2 Pd 2 Cd is a 1:1 intergrowth structure of CsCl and AlB 2 related slabs of compositions ‘YCd’ and ‘YPd 2 ’. The palladium dumb-bells (279 pm Pd–Pd) and the cadmium atoms (301 pm Cd–Pd) form a two-dimensional [Pd 2 Cd] substructure that is separated by yttrium layers in c direction. Consistent with their crystal structures, the 113 Cd solid-state MAS-NMR spectra of Y 2 Pd 2 Cd and isotypic Y 2 Cu 2 Cd show only one signal characterized by strong Knight shift contributions.