ausblenden:
Schlagwörter:
bond theory, half-Heusler phase, MgAgAs structure type, QTAIM, structure prediction
Zusammenfassung:
The chemical bonding of transition metal compounds with a MgAgAs-type of crystal structure is analyzed with quantum chemical position-space techniques. The observed trends in QTAIM Madelung energy and nearest neighbor electron sharing explain the occurrence of recently synthesized MgAgAs-type compounds, TiPtGe and TaIrGe, at the boundary to the TiNiSi-type crystal structure. These bonding indicators are used to identify favorable element combinations for new MgAgAs-type compounds. The new phases—the high-temperature VIrGe and the low-temperature HfPtGe—showing this type of crystal structure are prepared and characterized by powder X-ray diffraction and differential thermal analysis.
