• Gießelmann, Elias Carl Johannes

Abstract

<jats:title>Abstract</jats:title><jats:p>Single crystals of CaNi<jats:sub>2</jats:sub>Al<jats:sub>8</jats:sub> were obtained during attempts to synthesize CaNi<jats:sub>2</jats:sub>Al<jats:sub>9</jats:sub> from the elements in Nb or Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> crucibles in an induction furnace. The orthorhombic structure of CaNi<jats:sub>2</jats:sub>Al<jats:sub>8</jats:sub> was refined based on single-crystal X-ray diffraction data (<jats:italic>Pbam</jats:italic>, <jats:italic>a</jats:italic> = 1252.30(6), <jats:italic>b</jats:italic> = 1443.73(7), <jats:italic>c</jats:italic> = 395.78(2) pm, <jats:italic>wR</jats:italic>2 = 0.0423, 2225 <jats:italic>F</jats:italic><jats:sup>2</jats:sup> values, 63 variables) and full atomic ordering was observed. The compositions of the samples were checked by powder X-ray diffraction experiments; no phase pure samples could be obtained. To analyze the bonding situation of the title compound in detail, quantum-chemical calculations were conducted. According to Density Functional Theory, CaNi<jats:sub>2</jats:sub>Al<jats:sub>8</jats:sub> is a intermetallic compound with a polar covalently bonded [Ni<jats:sub>2</jats:sub>Al<jats:sub>8</jats:sub>] network showing strong Ni–Al and Al–Al bonding.</jats:p>

Topics

• density
• impedance spectroscopy
• compound
• single crystal
• phase
• theory
• experiment
• powder X-ray diffraction
• density functional theory
• intermetallic