caa a22 4500 463240219 CHVBK 20180405153310.0 cr unu---uuuuu 170326e20070901xx s 000 0 eng 10.1007/s10947-007-0121-x doi (NATIONALLICENCE)springer-10.1007/s10947-007-0121-x Non-empirical investigation of the geometrical structure and energy stability of dimers of yttrium β-diketonates Y2(MDA)6 and Y2(HFA)6 [Elektronische Daten] [V. Sliznev, S. Lapshina, G. Girichev] The structure of tris-complexes Y(MDA)3, Y(HFA)3 and their dimeric forms of Y2(MDA)6 and Y2(HFA)6 (MDA = C3O2H3; HFA = C5O2F6H) are investigated by the non-empirical Hartree-Fock method and also taking into account the correlation of electrons in the context of density functional theory (DFT/B3LYP) using effective pseudopotentials to describe the atomic core and double-exponential valence basis sets supplemented with polarization functions. For the first time the structure of Y(HFA)3, Y2(MDA)6, and Y2(HFA)6 molecules has been studied in this work. The equilibrium configuration of Y(HFA)3 monomer is a structure with a coordination polyhedron of [YO6] that has the form of a distorted octahedron with planar chelate fragments and CF3 substituents in which the C-F bond screens the C-C bond in the chelate fragment. The barrier of the internal rotation of one CF3 group is ∼3.0 kJ/mole (DFT/B3LYP). It is shown that rotations of CF3 groups in Y(HFA)3 molecule could be considered as mutually independent. The structures of C 1 and C 2 symmetry are the equilibrium configurations of Y2(MDA)6 and Y2(HFA)6 dimers respectively (DFT/B3LYP). The structure of the coordination polyhedron of [Y2O12] in C 1 and C 2 symmetry configurations can be represented as a combination of eight-and seven-coordinated polyhedra or two seven-coordinated polyhedra respectively. The energy stability of dimeric complexes is studied. According to DFT/B3LYP data, the dimerization energy equals −80.8 kJ/mole and −62.3 kJ/mole for Y2(MDA)6 and Y2(HFA)6 respectively. The force fields and frequencies of normal vibrations are calculated for the equilibrium configurations. The trends of changes in the vibrational spectra in Y(MDA)3→Y(HFA)3 and monomer→dimer transitions are discussed. The comparison with available experimental data is made. Springer Science+Business Media, Inc., 2007 quantum chemistry nationallicence non-empirical calculations nationallicence geometrical structure nationallicence vibrational spectra nationallicence intramolecular rearrangements nationallicence β-diketonates nationallicence dimer nationallicence transition metals nationallicence Sliznev V. Ivanovo State University of Chemistry and Technology, Russia aut Lapshina S. Ivanovo State University of Chemistry and Technology, Russia aut Girichev G. Ivanovo State University of Chemistry and Technology, Russia aut Journal of Structural Chemistry Springer US 48/5(2007-09-01), 796-810 0022-4766 48:5<796 2007 48 10947 https://doi.org/10.1007/s10947-007-0121-x text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10947-007-0121-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Sliznev V. Ivanovo State University of Chemistry and Technology, Russia aut NATIONALLICENCE 700 1- Lapshina S. Ivanovo State University of Chemistry and Technology, Russia aut NATIONALLICENCE 700 1- Girichev G. Ivanovo State University of Chemistry and Technology, Russia aut NATIONALLICENCE 773 0- Journal of Structural Chemistry Springer US 48/5(2007-09-01), 796-810 0022-4766 48:5<796 2007 48 10947 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer