Structure and vibrational assignment of magnesium acetylacetonate. A density functional theoretical study

The β-diketonates of various metals are interesting compounds from both applicative and theoretical point of view. These compounds have been used in the preparation of supported catalysts and as precursors of heterogeneous catalysts [1-5]. The volatility of some acetylacetonates makes possible their use for thin film formation with magnetic, electrical, and high-temperature superconductor properties, by metal-organic chemical vapor deposition techniques (MOCVD) [5-7]. Mg(acac)2 is an important source material for MgO films [7]. Gas-phase electron diffraction (E.D) study of Mg(acac)2 was performed by Zakharov et al. [8]. Junge and Musso [9] studied the infrared spectra of Mg(acac)2 and its 13C substituted analogue in the 1600–650 cm^−1 region. The results of 13C isotopic frequency shifts are very useful for interpretation of the vibrational spectra of Mg(acac)2. To our best knowledge, there is no study on the Far-IR or Raman spectra of Mg(acac)2. The aim of the present work is the full assignment of the vibrational spectra [harmonic wavenumbers, and relative intensities for Ramanand IR spectra] of Mg(acac)2 by means of density functional theory (DFT) levels. Attempts will also be made to study the efficiency of some popular DFT levels and basis sets in predicting the vibrationalfrequencies of the titled compound, which may be helpful in predicting the properties of similar complexes. The calculated vibrational frequencies are compared with those observed experimentally. The calculated band assignments at the DFT level are also compared with those given by Junge and Musso [9], based on isotopic substitution. The calculated geometrical parameters will be compared with the previously reported electron diffraction results [8].