摘要：

This paper reports on the synthesis and crystal structure analysis of palladium(II) bis-(trans-benzoyltrifluoroacetonate). Crystal data for PdO 4 C 20 F 6 H 12 :a= 4.748, b = 22.237, c = 9.410 , P = 105.44° Z = 2, space group P2 1 /c, d calc . = 1.86 g/cm . CAD-4 diffmctometer(MoKa), heavy atom method, R = 0.041 for 986 reflections. The structure is molecular ; the planar molecules are stacked. The Pd atom is surrounded by a square of four O atoms (PdO = 1.97 , chelate angle 94.4°); Pd is involved in additional intemctions with the C γ atoms of two neighboring molecules (Pd...C γ = 3.44 ). The molecular structure of palladium β-diketonate complexes, molecular packing in crystal, and intermolecular intemctions are considered. The van der Waals energies of the crystal lattice are calculated. The results are compared with the experimental values. In the structures of palladium( 11) β-diketonates, three groups of crystals are isolated: one group with 2 nearest-neighbor interactions (stacks), the second with 4 nearest-neighbor interactions (two-dimensional nets), and the third with 1 nearest-neighbor interaction (dimers). The latter are characteristic of the cis-complexes. The intemctions with 10–12 nearest neighbor molecules determine the energetics of the whole crystal. The high volatility of Pd(hfa) 2 is explained by the weaker intermolecular contacts between stacks in crystal.

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