Acid-base effects in hydrogen bonds in crystals

Ubbelohde, A. R.; Gallagher, K. J.

doi:10.1107/s0365110x55000340

Cited by 300 publications

(204 citation statements)

References 10 publications

Supporting

Mentioning

188

Contrasting

Unclassified

Order By: Relevance

“…H-bonded materials of intermediate strength such as large water clusters and ice at ambient pressure are predicted to exhibit a negligible Ubbelohde effect because in this regime QNEs have little influence on the intermolecular separations. Indeed this observation is consistent with experimental and theoretical observations for the ferroelectric H-bonded crystals, ice, and gas-phase dimers (20)(21)(22). We note that we have considered the "fm2" configuration of the formamide organic dimer (33), which has a blueshifted H-bond (as well as a redshifted one); the data in this case also agrees with the correlation we observe for the other H-bonded systems (Fig.…”

Section: Discussionsupporting

confidence: 80%

“…In H-bonded crystals, this effect is known as the Ubbelohde effect, where replacing H with deuterium (D) causes the O-O distance, and consequently the ferroelectric phase-transition temperature, to change (20). The conventional Ubbelohde effect yields an elongation of the O-O distances upon replacing H with D, although a negative Ubbelohde effect has also been observed (20,21).…”

mentioning

confidence: 97%

See 1 more Smart Citation

Quantum nature of the hydrogen bond

Walker

Michaelides

2011

Proc. Natl. Acad. Sci. U.S.A.

398

382

View full text Add to dashboard Cite

Hydrogen bonds are weak, generally intermolecular bonds, which hold much of soft matter together as well as the condensed phases of water, network liquids, and many ferroelectric crystals. The small mass of hydrogen means that they are inherently quantum mechanical in nature, and effects such as zero-point motion and tunneling must be considered, though all too often these effects are not considered. As a prominent example, a clear picture for the impact of quantum nuclear effects on the strength of hydrogen bonds and consequently the structure of hydrogen bonded systems is still absent. Here, we report ab initio path integral molecular dynamics studies on the quantum nature of the hydrogen bond. Through a systematic examination of a wide range of hydrogen bonded systems we show that quantum nuclear effects weaken weak hydrogen bonds but strengthen relatively strong ones. This simple correlation arises from a competition between anharmonic intermolecular bond bending and intramolecular bond stretching. A simple rule of thumb is provided that enables predictions to be made for hydrogen bonded materials in general with merely classical knowledge (such as hydrogen bond strength or hydrogen bond length). Our work rationalizes the influence of quantum nuclear effects, which can result in either weakening or strengthening of the hydrogen bonds, and the corresponding structures, across a broad range of hydrogen bonded materials. Furthermore, it highlights the need to allow flexible molecules when anharmonic potentials are used in force field-based studies of quantum nuclear effects.H ydrogen bonds are essential to life on earth. They are, for example, the main intermolecular interactions responsible for binding the two strands of DNA and holding together the condensed phases of water. H-bonds are also of great contemporary importance in nanoscience, being involved in, e.g., the functionalization and patterning of surfaces with ordered molecular overlayers (1, 2). It is known that H-bonds are complex and, in particular, because of the small mass of the proton it is often not appropriate to treat the proton in H-bonded systems as a classical particle. Instead the quantum nature of the proton must be taken into account and issues such as zero-point motion, quantum delocalization, and quantum tunneling are relevant. Recent advances in experimental techniques and the development of theoretical approaches (coupled with enormous advances in computer power) mean it is now possible to explore the quantum nature of the proton in H-bonded systems in exquisite detail. The relevance of quantum nuclear effects (QNEs) to liquid water and ice (3-8), interfacial water (9), and enzyme kinetics (10, 11) has recently been demonstrated. In particular, from first principles simulations by Morrone et al. (4,12) and neutron Compton scattering measurements by Burnham et al. (13,14), a clear picture of the impact of QNEs on the proton's real space delocalization and vibrational properties has been established. Upon increasing the H-bond strengt...

show abstract

Section: Discussionsupporting

confidence: 80%

mentioning

confidence: 97%

Quantum nature of the hydrogen bond

Walker

Michaelides

2011

Proc. Natl. Acad. Sci. U.S.A.

398

382

View full text Add to dashboard Cite

show abstract

“…Because of anharmonicity in the shape of the hydrogen bond potential energy well, the lower zero-point energy for deuterium results in a shorter O-D bond than the original O-H bond by 0.01-0.02 Å and a lengthening of the O⅐⅐⅐O distance by a similar magnitude (7,8,23,30). These geometric changes are readily detected by NMR for small molecules in aprotic organic solvents (8,31,32).…”

Section: Direct Detection Of Physical Coupling Between the Tyr-42 Andmentioning

confidence: 77%

Hydrogen bond dynamics in the active site of photoactive yellow protein

Sigala

Tsuchida

Herschlag

2009

Proc. Natl. Acad. Sci. U.S.A.

145

View full text Add to dashboard Cite

Hydrogen bonds play major roles in biological structure and function. Nonetheless, hydrogen-bonded protons are not typically observed by X-ray crystallography, and most structural studies provide limited insight into the conformational plasticity of individual hydrogen bonds or the dynamical coupling present within hydrogen bond networks. We report the NMR detection of the hydrogen-bonded protons donated by Tyr-42 and Glu-46 to the chromophore oxygen in the active site of the bacterial photoreceptor, photoactive yellow protein (PYP). We have used the NMR resonances for these hydrogen bonds to probe their conformational properties and ability to rearrange in response to nearby electronic perturbation. The detection of geometric isotope effects transmitted between the Tyr-42 and Glu-46 hydrogen bonds provides strong evidence for robust coupling of their equilibrium conformations. Incorporation of a modified chromophore containing an electron-withdrawing cyano group to delocalize negative charge from the chromophore oxygen, analogous to the electronic rearrangement detected upon photon absorption, results in a lengthening of the Tyr-42 and Glu-46 hydrogen bonds and an attenuated hydrogen bond coupling. The results herein elucidate fundamental properties of hydrogen bonds within the complex environment of a protein interior. Furthermore, the robust conformational coupling and plasticity of hydrogen bonds observed in the PYP active site may facilitate the larger-scale dynamical coupling and signal transduction inherent to the biological function that PYP has evolved to carry out and may provide a model for other coupled dynamic systems.charge delocalization ͉ hydrogen bond coupling ͉ protein structure ͉ signal transduction

show abstract

“…The origins of such an enormous isotopic effect however, remain contentious. Originally, a simple quantum model consisting of proton quantum-tunneling in a double-well potential was proposed to rationalise the T C observations (Blinc and Svetina, 1966); however, this simple model failed to explain the so-called Ubbelohde effect, which relates the experimentally observed elongation of H bonds upon deuteration to a purely geometric origin (Ubbelohde and Gallagher, 1955). Subsequently, models involving coupled vibrational lattice modes and proton dynamics were proposed (Dalal, Klymachyov, and Bussmann-Holder, 1998) that led to the conviction that quantum-tunneling effects were not necessary for explaining the isotopic influence on T C (McMahon et al, 1990).…”

Section: B H-bond Ferroelectricsmentioning

confidence: 99%

Simulation and understanding of atomic and molecular quantum crystals

2017

View full text Add to dashboard Cite

Quantum crystals abound in the whole range of solid-state species. Below a certain threshold temperature the physical behavior of rare gases ( 4 He and Ne), molecular solids (H 2 and CH 4 ), and some ionic (LiH), covalent (graphite), and metallic (Li) crystals can be only explained in terms of quantum nuclear effects (QNE). A detailed comprehension of the nature of quantum solids is critical for achieving progress in a number of fundamental and applied scientific fields like, for instance, planetary sciences, hydrogen storage, nuclear energy, quantum computing, and nanoelectronics. This review describes the current physical understanding of quantum crystals formed by atoms and small molecules, as well as the wide palette of simulation techniques that are used to investigate them. Relevant aspects in these materials such as phase transformations, structural properties, elasticity, crystalline defects and the effects of reduced dimensionality, are discussed thoroughly. An introduction to quantum Monte Carlo techniques, which in the present context are the simulation methods of choice, and other quantum simulation approaches (e. g., path-integral molecular dynamics and quantum thermal baths) is provided. The overarching objective of this article is twofold. First, to clarify in which crystals and physical situations the disregard of QNE may incur in important bias and erroneous interpretations. And second, to promote the study and appreciation of QNE, a topic that traditionally has been treated in the context of condensed matter physics, within the broad and interdisciplinary areas of materials science.

show abstract

Acid-base effects in hydrogen bonds in crystals

Cited by 300 publications

References 10 publications

Quantum nature of the hydrogen bond

Quantum nature of the hydrogen bond

Hydrogen bond dynamics in the active site of photoactive yellow protein

Simulation and understanding of atomic and molecular quantum crystals

Contact Info

Product

Resources

About