Hydrogen bridges of polycyclic aromatic systems with O-H···O bonds — a gas-phase vs. solid-state Car-Parrinello study

Abstract

The current study belongs to a series of investigations of polycyclic aromatic compounds containing intramolecular hydrogen bonds. Close proximity of the coupled aromatic system and hydrogen bridges gives rise to resonance-assisted hydrogen bonding phenomena. Substituted naphthols are ideally suited for this kind of investigation. The parent compound, 1-hydroxy-8-methoxy-3-methylnaphthalene, and its derivative, 1-bromo-5-hydroxy-4-isopropoxy-7-methylnaphthalene, both with known crystal structure, are investigated. Car-Parrinello molecular dynamics (CPMD) is chosen as a theoretical background for this study. Gas phase and solid state simulations are carried out. The effect of Grimme’s dispersion corrections is also included. The report presents time evolution of structural parameters, spectroscopic signatures based on the CPMD simulations, and comparison with available experimental data. We show that the proton transfer phenomena do not occur within the simulations, which is consistent with evaluation based on the acidity of the donor and acceptor sites. The effects of the substitution in the aromatic system and change of the environment (gas vs. condensed phase) are of similar magnitude.

Maleimide: a potential building block for the design of proton exchange membranes studied by ab initio molecular dynamics simulations

“…4a are scaled by factors of 1.0376. 43,55 For the spectrum of C-H bond, the major peak at 3152 cm À1 is consistent with the corresponding FTIR peak at about 3100 cm À1 . For the N-H spectrum, the major peak at 3264 cm À1 is much broader than the C-H peak revealing the strong intermolecular H-bonding interaction between N-H and the acyl oxygen atom.…”

“…On the other hand, a simulation with only one unit cell is sufficient to reproduce the characteristic of proton transport despite of the fact that statistical errors may be signicant for quantitative values. [41][42][43][44] The generalized gradient approximation (GGA) functionals and hybrid functionals are widely accepted in quantum chemistry calculations because these functionals can provide reasonably accurate predictions for geometries and thermodynamics of small covalent molecules. [45][46][47] In our CPMD simulations, the hybrid BLYP exchange-correlation functionals are used to approximate the energy of valent electrons, 48 which can provide an adequate description of crystalline systems with H-bonding, 31,32,49 the Troullier-Martins (MT) norm-conserving pseudo-potentials are used to represent the core electrons, 50 and the plane wave basis set is used to expand the Kohn-Sham wave functions with a cutoff energy at 85 Rydberg.…”

Cation–π interactions in competition with cation microhydration: a theoretical study of alkali metal cation–pyrene complexes

“…7). The electrostatic potential is a useful physical property, and calculated values of it (e.g., on a molecular surface) can indicate which parts of a molecular system are important for nonbonding interactions [54]. The calculated electrostatic potential was mapped onto the 0.001 e /bohr 3 electron density isosurfaces for the structures at the global minima of the potential energy curves, i.e., the outer complex for the Li + case and the inner complex for K + (Figs.…”

Investigations of the hydrogen bond in the crystals of tropolone and thiotropolone via car‐parrinello and path integral molecular dynamics

“…Therefore, the continuous development of theoretical quantum methods, especially molecular dynamics methods, allows accurate prediction and description of chemical mechanisms, including the mechanism of proton transfer. There have been several recent experimental and theoretical studies on PT in the solid state in molecular crystals and other solid systems like several acid crystal hydrates which have given rise to the discuss about the same nature of proton transfer mechanism, values of the barrier height of PT, about attempts to estimate the time frame of the PT phenomenon, about how the rapid movement of the proton interfaces with the slow motions of the molecular skeleton and as a consequence about nature of hydrogen bonds with existing fast proton transfer (FPT).…”