The molecular structure of Mg(acac)2 determined by gas-phase electron diffraction and quantum mechanical calculations

The molecular structure of magnesium bis-acetylacetonate has been determined by synchronous gas-phase electron diffraction (GED) and mass spectrometric experiment and quantum mechanical calculations (HF/6-311 þ G(d,p), B3LYP/6-311 þ G(d,p), and MP2/6-311 þ G(d,p)). Both experimental and theoretical approaches yielded the structure of D2d symmetry with chelate rings located in perpendicular planes. Major structural parameters determined by GED experiment are the following: bond distances ra(Mg–O) ¼ 1.966(4), ra(O–C) ¼ 1.279(2), ra(C–C0) ¼ 1.408(3), ra(C–Cm) ¼ 1.534(4) A ° ; valence angles /a(O–Mg–O) ¼ 93.3(2), /a(O–C0–C) ¼ 125.3(2), /a(O–C–Cm) ¼ 116.2(4)8. q 2004 Elsevier B.V. All rights reserved.