A search has been conducted, employing ab initio molecular orbital theory, for potential tetrel-bonded complexes between the fluorinated methanes methyl fluoride, difluoromethane and fluoroform, and the related hydrides ammonia, water, hydrogen fluoride, phosphine, hydrogen sulfide and hydrogen chloride. Eleven such complexes have been identified, six containing CH3F and five CH2F2. The complexes are typically less strongly bound than their hydrogen-bonded counterparts, and the interaction energies vary in a consistent way with the periodic trend of the electron donors. The intermolecular separations and changes of the relevant intramolecular bond lengths, the wavenumber shifts of the critical vibrational modes, and the extents of charge transfer for the atoms most closely involved in the interactions correlate, by and large, with the strengths of interaction.

The bonding evolution theory has been used to investigate the flow of electron density along the reaction pathways of ethyl acetate 2-oxo-2-(4-oxo-4H-pyrido [1.2-a] pyrimidin-3-yl) polyazaheterocycle (1) and ethylenediamine (2). This reaction has three channels (1-3) and each one takes place via three or four steps. DFT results reveal that channel 2, which goes through imine intermediate is by far the most favorable one, and the main product 3 is more stable than 4 and 5, showing that this reaction is under kinetic and thermodynamic control, in clear agreement with the experimental outcomes. The BET analysis allows identifying unambiguously the main chemical events happening along channel 2. For this reaction channel, the mechanism along the first step (TS2-a) is described by a series of four structural stability domains (SSDs), while five SSDs are required for the second (TS2-b) and the third (TS2-c) one. The first step can be summarized as follow, the appearance of V(N1,C6) basin illustrating the formation of N1-C6 bond (SSD-II), the splitting of N1-H1 bond, followed by the restoration of the nitrogen N1 lone pair (SSD-III), and finally, the formation of the last O1-H1 bond (SSD-IV). For the second step, the formation of hydroxide ion is noted, consequent of the disappearance of V(C6,O7) basin, the transformation of C6-N1 single bond into double one (SSD-IV). Finally, the appearance of V(O7,H2) basin leading to the elimination of water molecule within the last domain. Overall, for the three reaction steps, the formation of the N-C bond appears always before the O-H one.