Impacts of hydrogen bonding interactions with Np(v/vi)O₂Cl₄ complexes: vibrational spectroscopy, redox behavior, and computational analysis

Abstract

Crystallization of neptunyl(v) tetrachlorides over neptunyl(vi) species occurs simultaneously with charge assisted hydrogen bonding in our solid state materials, which we explored by DFT calculations, cyclic voltammograms, and Raman spectroscopy.

Impact of Noncovalent Interactions on the Structural Chemistry of Thorium(IV)-Aquo-Chloro Complexes

“…Vibrational spectroscopy not only is thus a valuable tool to understand the structure–property relationships in Th IV hybrid materials but also may be useful in probing the influence of noncovalent interactions on metal bonding. Raman spectroscopy in particular has been used to examine the impact of outer sphere H-bonding on the vibrational shifts of An–ligand bonding, albeit much more successfully with actinyl compounds. , …”

Periodic Density Functional Theory Calculations of Uranyl Tetrachloride Compounds Engaged in Uranyl–Cation and Uranyl–Hydrogen Interactions: Electronic Structure, Vibrational, and Thermodynamic Analyses

“…61,62 The engagement of the oxo group in NCIs can result in shifting of these vibrational energies or the activation of additional bands due to U�O yl bond perturbation and weakening. 16,24,25 Experimentally, optical scattering occurs near the Γ point in the Brillouin zone; therefore, we calculated the corresponding phonon eigenvalues and eigenvectors of the Hessian matrix at this point to investigate the uranyl−cation and uranyl− hydrogen vibrational spectra. As explained above, group theory can be used to determine the total number of IR and Raman active modes in each system, 63 while the intensities of each mode can, in principle, be calculated using density functional perturbation theory (DFPT).…”

“…Additionally, efforts will further be needed to understand related Np and Pu systems to provide added insights into the electronic structure of f -block elements. Only a handful of related Np compounds have been reported in the literature, but these systems display enhanced NCIs compared to their uranyl counterparts. ,,, However, the experimental determination of Δ H f of neptunyl can be far more challenging than that of uranyl systems due to limited availability, high cost, and the increased radioactivity of neptunium-237.…”

Use of vibrational spectroscopy to identify the formation of neptunyl–neptunyl interactions: a paired density functional theory and Raman spectroscopy study

“…3,4 The strength of AnvO yl bonds are important to understanding the chemistry of these systems and is the subject of extensive experimental and theoretical studies to understand its electronic structure. [5][6][7][8][9][10][11][12] In addition, this particular bonding motif imparts significant influence on the chemistry in aqueous and solid-state systems, resulting in overall changes in its redox properties, 13,14 disproportionation reactions, 15 and complex vibrational and electronic spectroscopy. 13,14,16,17 Therefore, it is crucial to understand both the bonding within the actinyl cation and the additional interactions within the solid and solution phases to develop an in-depth, systems-level approach to the chemistry of the high-valent early actinides.…”

“…The symmetry of the system can be perturbed through intermolecular interactions involving the oxo groups, such as actinyl-cation (ACI), actinyl-hydrogen (AHI) and actinyl-actinyl (AAI) interactions, and lead to significant complexity within the vibrational spectra. 14,16,[23][24][25][26][27] Of particular note is AAI interactions (also known as cation-cation interactions or CCIs) because there is a significant amount of spectral complexity observed within the window of interest (600-900 cm −1 ). 28,29 Within systems containing Np(V)O 2 + , the increased Lewis basicity of the oxo groups results in a greater propensity of the neptunyl(V) unit to engage in AAIs.…”