Energetic and topological analysis of the reaction of Mo and Mo₂ with NH₃, C₂H₂, and C₂H₄ molecules

Abstract

The Density functional theory has been applied to characterize the structural features of Mo(1,2)-NH(3),-C(2)H(4), and -C(2)H(2) compounds. Coordination modes, geometrical structures, and binding energies have been calculated for several spin multiplets. It has been shown that in contrast to the conserved spin cases (Mo(1,2)-NH(3)), the interaction between Mo (or Mo(2)) and C(2)H(4) (or C(2)H(2)) are the low-spin (Mo-C(2)H(4) and -C(2)H(2)) and high-spin (Mo(2)-C(2)H(4) and -C(2)H(2)) complexes. In the ground state of Mo(1,2)-C(2)H(4) and -C(2)H(2), the metal-center always reacts with the C-C center. The spontaneous formation of the global minima is found to be possible due to the crossing between the potential energy surfaces (ground and excited states with respect to the metallic center). The bonding characterization has been performed using the topological analysis of the Electron Localization Function. It has been shown that the most stable electronic structure for a pi-acceptor ligand correlates with a maximum charge transfer from the metal center to the C-C bond of the unsaturated hydrocarbons, resulting in the formation of two new basins located on the carbon atoms (away from hydrogen atoms) and the reduction of the number of attractors of the C-C basin. The interaction between Mo(1,2) and C(2)H(4) (or C(2)H(2)) should be considered as a chemical reaction, which causes the multiplicity change. Contrarily, there is no charge transfer between Mo(1,2) and NH(3), and the partners are bound by an electrostatic interaction.

Energetic and topological analyses of the oxidation reaction between Mon (n = 1, 2) and N2O

“…In a previous article,13 we have already checked the reliability of the level of theory employed in the present work by studying the bare molybdenum atom and dimer. For the energetic gap between the first excited state ( 5 S ( d 5 s 1 )) and the ground state ( 7 S ( d 5 s 1 )) of Mo, the PW91PW91/LANL2DZ level of theory is the one that better reproduce the measured value (1.38, 1.45, 1.42, and 1.33 eV, the PW91PW91,13 CI,37 BPW91,38 and experimental39 values, respectively).…”

“…In a recent work,13 we have presented an energetic and topological study of the adduct formation process for the interaction of Mo and Mo 2 with different small ligands, namely NH 3 , C 2 H 2 , and C 2 H 4 . We have shown that Mo and Mo 2 essentially interact with C 2 H 2 and C 2 H 4 via an electron pair transfer from the metallic‐center to the ligand, forming a chemical bond with the carbon atoms, while the interaction between Mo (or Mo 2 ) and NH 3 has mostly an electrostatic character.…”

Describing the Molecular Mechanism of Organic Reactions by Using Topological Analysis of Electronic Localization Function

“…BET [37] has been applied to different elementary reactions as proton transfers [36,58], isomerisations [59], electron transfers [60] and studies on two-state reactivity [61][62][63]. A systematic investigation of the mechanism of important organic reactions such as the Diels-Alder reactions [45,46] the 1,3-dipolar reaction between fulminic acid and acetylene [44], the molecular mechanism of the Bergman cyclization [64], the trimerization of acetylene [65] the "chameleonic vs centauric" mechanisms of the Cope rearrangement of 1,5 hexadiene and its cyano derivatives [66] the Nazarov cyclization [67] and the S N 2 reaction [68].…”

The ELF Topological Analysis Contribution to Conceptual Chemistry and Phenomenological Models

“…The ELF topology has been extensively used for study of chemical bonding , aromaticity problems [81][82][83][84][85][86][87][88], reactivity [89][90][91], and chemical reactions [92][93][94][95][96][97][98][99][100][101][102][103][104][105]. Several review papers have already been published [86,[106][107][108].…”