Molecular structure of N,N′-o-phenylene-bis(salicylideneaminato)zinc(II), Zn(saloph), according to gas-phase electron diffraction and quantum-chemical calculations

The molecular structure of N,N′-o-phenylene-bis(salicylideneaminato)zinc(II) has been determined by synchronous gas-phase electron diffraction (GED) and mass spectrometric experiment at 626(5) K and by density functional theory calculations (B3LYP/Stuttgart ECP(Zn), TZV (O, N, C, H) with the addition of d-polarization functions; in case of N, O with the addition of p-diffuse functions; B3LYP/Stuttgart ECP(Zn), cc-pVTZ (O, N, C, H)). Both experimental and theoretical approaches yielded the structure of Cs-symmetry with a planar ZnN2O2 coordination site. The overall ligand conformation is also planar with small distortion towards an umbrella-shape. The most important structure parameters are rh1(Zn-N) = 2.072(12) Å; rh1(Zn-O) = 1.926(7) Å; ∠NZnN = 77.4(1.4)°; ∠NZnO = 90.4(1.4)°; ∠OZnO = 101.9(2.5)°. Structural features of tetra-coordinate zinc complexes are discussed.