Is There an Adduct of Pyridine -Oxide and Boron Trifluoride in the Gaseous State? Gas Electron Diffraction vs Mass Spectrometry.

A study of saturated vapor over the pyridine -oxide-boron trifluoride (PyO-BF) adduct was carried out at = 448(5) K by a synchronous gas electron diffraction/mass spectrometry (GED/MS) experiment. Due to the absence of ions in the mass spectrum, indicating the presence of a structure with an O-B dative bond, several models of vapor composition were tested by the GED method. It was found that the dominant molecular form (up to 100%) in vapor is the PyO-BF adduct.

First Examples of -Metal Complexes with Subporphyrazine and Its Phenylene-Annulated Derivatives: DFT Calculations.

Using quantum chemical calculation data obtained by the DFT method with the B3PW91/TZVP and M062X/def2TZVP theory levels, the possibility of the existence of four Be(II) coordination compounds, each of which contains in the inner coordination sphere and the double deprotonated forms of subporphyrazine (H), mono[benzo]subporphyrazine (H), di[benzo]subporphyrazine (H), and tri[benzo]subporphyrazine (subphthalocyanine) (H) with a ratio Be(II) ion/ligand = 1:1, were examined Selected geometric parameters of the molecular structures of these (666)macrotricyclic complexes with closed contours are given; it was noted that BeN3 chelate nodes have a trigonal-pyramidal structure and exhibit a very significant (almost 30°) deviation from coplanarity; however, all three 6-membered metal-chelate and three 5-membered non-chelate rings in each of these compounds are practically planar and deviate from coplanarity by no more than 2.5°. The bond angles between two nitrogen atoms and a Be atom are equal to 60° (in the [Be] and [Be]) or less by no more than 0.

The Perfluoro-o-phenylene-mercury Trimer [Hg(o-CF)] - a Textbook Example of Phase-Dependent Structural Differences.

The geometric and electronic structure of [Hg(o-CF)] (1) in the gas phase, i. e. free of intermolecular interactions, was determined by a synchronous gas-phase electron diffraction/mass spectrometry experiment (GED/MS), complemented by quantum chemical calculations.

Molecular Structure of Gaseous Oxopivalate Co(II): Electronic States of Various Multiplicities.

Synchronous electron diffraction/mass spectrometry was used to study the composition and structure of molecular forms existing in a saturated vapor of cobalt(II) oxopivalate at T = 410 K. It was found that monomeric complexes CoO(piv) dominate in the vapor. The complex geometry possesses the C symmetry with bond lengths Co-O = 1.

Dimer Rhenium Tetrafluoride with a Triple Bond Re-Re: Structure, Bond Strength.

Based on the data of the gas electron diffraction/mass spectrometry (GED/MS) experiment, the composition of the vapor over rhenium tetrafluoride at T = 471 K was established, and it was found that species of the ReF is present in the gas phase. The geometric structure of the ReF molecule corresponding to D symmetry was found, and the following geometric parameters of the r configuration were determined: r(Re-Re) = 2.264(5) Å, r(Re-F) = 1.