Ground and excited states of vanadium hydroxide isomers and their cations, VOH0,+ and HVO0,+

Abstract

Employing correlation consistent basis sets of quadruple-zeta quality and applying both multireference configuration interaction and single-reference coupled cluster methodologies, we studied the electronic and geometrical structure of the [V,O,H](0,+) species. The electronic structure of HVO(0,+) is explained by considering a hydrogen atom approaching VO(0,+), while VOH(0,+) molecules are viewed in terms of the interaction of V(+,2+) with OH(-). The potential energy curves for H-VO(0,+) and V(0,+)-OH have been constructed as functions of the distance between the interacting subunits, and the potential energy curves have also been determined as functions of the H-V-O angle. For the stationary points that we have located, we report energies, geometries, harmonic frequencies, and dipole moments. We find that the most stable bent HVO(0,+) structure is lower in energy than any of the linear HVO(0,+) structures. Similarly, the most stable state of bent VOH is lower in energy than the linear structures, but linear VOH(+) is lower in energy than bent VOH(+). The global minimum on the potential energy surface for the neutral species is the X(3)A" state of bent HVO, although the X(5)A" state of bent VOH is less than 5 kcal/mol higher in energy. The global minimum on the potential surface for the cation is the X(4)Σ(-) state of linear VOH(+), with bent VOH(+) and bent HVO(+) both more than 10 kcal/mol higher in energy. For the neutral species, the bent geometries exhibit significantly higher dipole moments than the linear structures.

On the linear geometry of lanthanide hydroxide (Ln-OH, Ln = La–Lu)

“…Those systems feature s bond donation from an oxygen lone pair to the empty metal 3dz2 orbital, as well as donation of two additional oxygen lone pairs to metal 3dxz and 3dyz orbitals. Thus, the bond order in those systems is 3, [42][43][44] just as our results suggest for LnOH.…”

“…Relating this result to the well-studied structure and bonding of transition metal hydroxides, [42][43][44][45][46][47][48][49][50] we observe a similarity with early transition metal hydroxide bonding. Specifically, we show that the nature of the lanthanide hydroxide bond involves important π-bonding.…”

Methane to Methanol Conversion Facilitated by Transition-Metal Methyl and Methoxy Units: The Cases of FeCH3+ and FeOCH3+

“…The correlation consistent basis sets of triple-ζ (TZ) quality were employed (cc-pVTZ). , For the oxygen centers, we added a series of diffuse functions (aug-cc-pVTZ) to account for the ionic nature of the iron–oxygen bonds. − In some computationally demanding cases, we used double-ζ (DZ) quality.…”